Definition of cosine The cosine of an angle is defined as the sine of the complementary angle. The complementary angle equals the given angle subtracted from a right angle, 90°. For instance, if the angle is 30°, then its complement is 60°. Generally, for any angle θ, cos θ = sin (90° – θ).Cos 25 degrees is the value of cosine trigonometric function for an angle equal to 25 degrees. The value of cos 25° is 0.9063 (approx) How to Find Cos 25° in Terms of Other Trigonometric Functions? Using trigonometry formula, the value of cos 25° can be given in terms of other trigonometric functions as: ± √(1-sin²(25°)) Maths Math Article Trigonometric Functions Value Of Cos 60 Value of cos 60 The value of cos 60 is 1/2. Trigonometry is used to study the measurements of right-angled triangles that deals with the parameters such as length, height and angles of the triangle. It has an enormous application in the real world.Important Angles: 30°, 45° and 60° You should try to remember sin, cos and tan for the angles 30 ° , 45 ° and 60 ° . Yes, yes, it is a pain to have to remember things, but it will make life easier when you know them, not just in exams, but other times when you need to do quick estimates, etc.The displacement h (t), h (t), in centimeters, of a mass suspended by a spring is modeled by the function h (t) = −5 cos (60 π t), h (t) = −5 cos (60 π t), where t t is measured in seconds. Find the amplitude, period, and frequency of this displacement.tan(60 degrees ) 17: Find the Exact Value: sec(30 degrees ) 18: Find the Exact Value: cos(60 degrees ) 19: Find the Exact Value: cos(150) 20: Find the Exact Value: sin(60) 21: Find the Exact Value: cos(pi/2) 22: Find the Exact Value: tan(45 degrees ) 23: Find the Exact Value: arctan(- square root of 3) 24: Find the Exact Value: csc(60 degrees ... Tan 60 0 = AD/BD. = a√3/a = √3. Therefore, tan 60 degrees exact value is given by, Tan 60 0 =√3. In the same way, we can derive other values of tan degrees like 0 °, 30 °, 45 °, 90 °, 180 °, 270 ° and 360 °. Below is the trigonometry table, which defines all the values of tan along with other trigonometric ratios.Cos 300 degrees is the value of cosine trigonometric function for an angle equal to 300 degrees. The value of cos 300° is 1/2 or 0.5 . What is the Value of Cos 300 Degrees in Terms of Sin 300°? Using trigonometric identities, we can write cos 300° in terms of sin 300° as, cos(300°) = √(1 - sin²(300°)). Here, the value of sin 300° is ... The ratios of the sides of a right triangle are called trigonometric ratios. Three common trigonometric ratios are the sine (sin), cosine (cos), and tangent (tan). These are defined for acute angle A A below: In these definitions, the terms opposite, adjacent, and hypotenuse refer to the lengths of the sides.Aug 23, 2012 · I have noticed that students cannot actually remember values of six trigonometric ratios (sin, cos, tan, cosec, sec and cot) for 0. , 30. , 45. , 60. and 90. . These values are used very often and it is recommended from my point of view that student should be able to tell the values instantly when asked. There is a proper method to memorize all ... Free math problem solver answers your algebra, geometry, trigonometry, calculus, and statistics homework questions with step-by-step explanations, just like a math tutor.I have noticed that students cannot actually remember values of six trigonometric ratios (sin, cos, tan, cosec, sec and cot) for 0. , 30. , 45. , 60. and 90. . These values are used very often and it is recommended from my point of view that student should be able to tell the values instantly when asked. There is a proper method to memorize all ...Sep 23, 2019 · In this video, we learn to find the value of cos(-60). Here I have applied cos(-x) = cos(x) identity to find the value of cosine of -60 degree. The URL of th... Trigonometry. Find the Exact Value cos (60 degrees ) Step 1. The exact value of is . Step 2. The result can be shown in multiple forms. Exact Form:\begin{equation} \cos^2 \theta_x + \cos^2 \theta_y +\cos^2 \theta_z = 1\tag{2.5.3} \end{equation} This page titled 2.5: Unit Vectors is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Daniel W. Baker and William Haynes ( Engineeringstatics ) via source content that was edited to the style and standards of the ...Question 1) Give a short derivation of cos 60 degree. Solution) Let us consider a right- angled triangle with one angle as 60°. The other two angles of the triangle are 90°,30° . For a triangle with angles 60°,90°,30° the sides are always in the ratio 1: 2: 3–√ 3. In a right –angled triangle,This formula can be simplified to −sin60 = − 23 Explanation: sin20cos80−cos20sin80 = sin(20 −80)= sin(−60)= −sin60 = − 23. How do you find the exact value of sin45cos 30 − cos45sin30 using the sum and difference, double angle or half angle formulas? sin15 = ( 42)( 3 −1) Explanation: Use trig identity: sin (a - b) = sin a.cos b ...Free math problem solver answers your algebra, geometry, trigonometry, calculus, and statistics homework questions with step-by-step explanations, just like a math tutor.What are the exact values of cos150° and sin150° ? cos150 = − 23 sin150 = 21 Explanation: Use trig table and unit circle --> cos150 = cos(−30+180) = −cos(−30)= ... Calculate the value of the cos of 1.5 ° To enter an angle in radians, enter cos (1.5RAD) cos (1.5 °) = 0.999657324975557 Cosine the trigonometric function that is equal ... What is tan 30 using the unit circle? tan 30° = 1/√3. To find this answer on the unit circle, we start by finding the sin and cos values as the y-coordinate and x-coordinate, respectively: sin 30° = 1/2 and cos 30° = √3/2. Now use the formula. Recall that tan 30° = sin 30° / cos 30° = (1/2) / (√3/2) = 1/√3, as claimed.Free math problem solver answers your algebra, geometry, trigonometry, calculus, and statistics homework questions with step-by-step explanations, just like a math tutor.Free trigonometric simplification calculator - Simplify trigonometric expressions to their simplest form step-by-step cos (135) cos ( 135) Apply the reference angle by finding the angle with equivalent trig values in the first quadrant. Make the expression negative because cosine is negative in the second quadrant. −cos(45) - cos ( 45) The exact value of cos(45) cos ( 45) is √2 2 2 2. − √2 2 - 2 2. The result can be shown in multiple forms.Explanation: Imagine the unit circle: We know that 300∘ is in the fourth quadrant, where cosine is positive. 300∘ has a reference angle of 60∘, since it is 60∘ away from the x -axis. Since cos(60∘) = 1 2, we know that cos(300∘) = 1 2 as well since cos(θ) > 0 in the fourth quadrant. Answer link.Cos 300 degrees is the value of cosine trigonometric function for an angle equal to 300 degrees. The value of cos 300° is 1/2 or 0.5 . What is the Value of Cos 300 Degrees in Terms of Sin 300°? Using trigonometric identities, we can write cos 300° in terms of sin 300° as, cos(300°) = √(1 - sin²(300°)). Here, the value of sin 300° is ...Answer of given expression is sin(-60°) What is Trigonometric functions? Trigonometric functions defined as the functions which show the relationship between angle and sides of a right-angled triangle. Given expression, sin(20°)cos(80°) – cos(20°)sin(80°) ∵ sin(A-B) = sinA.cosB – cosA.sinB. ∴ sin(20°-80°) So, sin(-60°)Free trigonometric simplification calculator - Simplify trigonometric expressions to their simplest form step-by-stepSine and cosine are written using functional notation with the abbreviations sin and cos. Often, if the argument is simple enough, the function value will be written without parentheses, as sin θ rather than as sin(θ). Each of sine and cosine is a function of an angle, which is usually expressed in terms of radians or degrees. Except where ...cos (105) cos ( 105) Apply the reference angle by finding the angle with equivalent trig values in the first quadrant. Make the expression negative because cosine is negative in the second quadrant. −cos(75) - cos ( 75) Split 75 75 into two angles where the values of the six trigonometric functions are known. −cos(30+ 45) - cos ( 30 + 45 ...Feb 21, 2017 · Exact values of sin(60), cos(60), tan(60), csc(60), sec(60), cot(60), Find exact values of all trigonometric functions when the angle is 60 degrees,blackpenr... What are the exact values of cos150° and sin150° ? cos150 = − 23 sin150 = 21 Explanation: Use trig table and unit circle --> cos150 = cos(−30+180) = −cos(−30)= ... Calculate the value of the cos of 1.5 ° To enter an angle in radians, enter cos (1.5RAD) cos (1.5 °) = 0.999657324975557 Cosine the trigonometric function that is equal ... Q. Evaluate sin60∘ cos30∘ +cos60∘sin30∘. Q. Evaluate each of the following. sin 60 cos 30° + cos 60° sin 30°. Q. Find the values of -. (i) 5 sin 30 ° + 3 tan 45 ° (ii) 4 5 tan 2 60 ° + 3 sin 2 60 ° (iii) 2sin 30 ° + cos 0 ° + 3sin 90°. (iv) tan 60 sin 60 + cos 60 (v) cos 2 45 ° + sin 2 30 ° (vi) cos 60 ° × cos 30 ° + sin ...Sine and cosine are written using functional notation with the abbreviations sin and cos. Often, if the argument is simple enough, the function value will be written without parentheses, as sin θ rather than as sin(θ). Each of sine and cosine is a function of an angle, which is usually expressed in terms of radians or degrees. Except where ...Jun 10, 2021 · What is quadrantal angle? A Quadrantal angle is an angle that is not in Quadrant I. Consider angle 120. You want to find cos (120) . 120 lies in quadrant II. Also, 120=180-60. So, it is enough to find cos (60) and put the proper sign. cos (60)=1/2. Cosine is negative in quadrant II, Therefore, cos (120) = -1/2. Maths Math Article Trigonometric Functions Value Of Cos 60 Value of cos 60 The value of cos 60 is 1/2. Trigonometry is used to study the measurements of right-angled triangles that deals with the parameters such as length, height and angles of the triangle. It has an enormous application in the real world. double cos (double x); float cosf (float x);long double cosl (long double x); ... The cosine of 60.000000 degrees is 0.500000. See also sin Compute sine (function) tanMaths Math Article Trigonometric Functions Value Of Cos 60 Value of cos 60 The value of cos 60 is 1/2. Trigonometry is used to study the measurements of right-angled triangles that deals with the parameters such as length, height and angles of the triangle. It has an enormous application in the real world. The cosine function is an even function because cos (− θ) = cos θ. cos (− θ) = cos θ. For example, consider corresponding inputs π 4 π 4 and − π 4. − π 4. The output of cos (π 4) cos (π 4) is the same as the output of cos (− π 4). cos (− π 4). Thus,\begin{equation} \cos^2 \theta_x + \cos^2 \theta_y +\cos^2 \theta_z = 1\tag{2.5.3} \end{equation} This page titled 2.5: Unit Vectors is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Daniel W. Baker and William Haynes ( Engineeringstatics ) via source content that was edited to the style and standards of the ...Definition of cosine The cosine of an angle is defined as the sine of the complementary angle. The complementary angle equals the given angle subtracted from a right angle, 90°. For instance, if the angle is 30°, then its complement is 60°. Generally, for any angle θ, cos θ = sin (90° – θ).For memorising cos 0°, cos 30°, cos 45°, cos 60° and cos 90°. Cos is the opposite of sin. We should learn it like. cos 0° = sin 90° = 1. cos 30° = sin 60° = √3/2. cos 45° = sin 45° = 1/√2. cos 60° = sin 30° = 1/2. cos 90° = sin 0° = 0. So, for cos, it will be like.Sin 60 = √3/2. Sin 90 = 1. Fact: The values sin 30 and cos 60 are equal. Sin 30 = Cos 60 = ½. And. Cosec 30 = 1/Sin 30. Cosec 30 = 1/(½) Cosec 30 = 2. Derivation to Find the Sin 30 value (Geometrically) Let us now calculate the sin 30 value. Consider an equilateral triangle ABC. Since each angle in an equilateral triangle is 60°, therefore The displacement h (t), h (t), in centimeters, of a mass suspended by a spring is modeled by the function h (t) = −5 cos (60 π t), h (t) = −5 cos (60 π t), where t t is measured in seconds. Find the amplitude, period, and frequency of this displacement. Tentukan Nilai yang Tepat cos(-60 derajat ) Step 1. Terapkan sudut acuan dengan mencari sudut dengan nilai-nilai-trigonometri yang setara di kuadran pertama.Tan 60° = AD/BD = √3 / 1 = √3. We can also write the value of cos 60 degrees in decimal form as: cos 60° = 1/2 = 0.5. Also, we can write the values of sine, cosine and tangent with respect to all the degrees in a table. Let us draw a table with respect to degrees and radians for sine, cosine and tangent functions.240^o has a reference angle of 60^o as indicated in the image below. A 60^o angle is a basic angle from one of the common triangles: From their definitions: sin(240^o) = -sqrt(3)/2 cos(240^o) = -1/2 tan(240^o) = sqrt(3) csc(240^o) = - 2/sqrt(3) sec(240^o) = -2 cot(240^o) = 1/sqrt(3)Aug 4, 2016 · Explanation: Imagine the unit circle: We know that 300∘ is in the fourth quadrant, where cosine is positive. 300∘ has a reference angle of 60∘, since it is 60∘ away from the x -axis. Since cos(60∘) = 1 2, we know that cos(300∘) = 1 2 as well since cos(θ) > 0 in the fourth quadrant. Answer link. What is quadrantal angle? A Quadrantal angle is an angle that is not in Quadrant I. Consider angle 120. You want to find cos (120) . 120 lies in quadrant II. Also, 120=180-60. So, it is enough to find cos (60) and put the proper sign. cos (60)=1/2. Cosine is negative in quadrant II, Therefore, cos (120) = -1/2.Free trigonometric function calculator - evaluate trigonometric functions step-by-step Aug 14, 2023 · What is tan 30 using the unit circle? tan 30° = 1/√3. To find this answer on the unit circle, we start by finding the sin and cos values as the y-coordinate and x-coordinate, respectively: sin 30° = 1/2 and cos 30° = √3/2. Now use the formula. Recall that tan 30° = sin 30° / cos 30° = (1/2) / (√3/2) = 1/√3, as claimed. Feb 21, 2023 · Because cos () is a static method of Math, you always use it as Math.cos (), rather than as a method of a Math object you created ( Math is not a constructor). Online cosine calculator. Accepts values in radians and in degrees. Free online cosine calculator. cos(x) calculator.Sin 60° = AD/AB = √3/2. Tan 60° = AD/BD = √3 / 1 = √3. We can also write the value of cos 60 degrees in decimal form as: cos 60° = 1/2 = 0.5. Also, we can write the values of sine, cosine and tangent with respect to all the degrees in a table.Free trigonometric simplification calculator - Simplify trigonometric expressions to their simplest form step-by-step Free trigonometric simplification calculator - Simplify trigonometric expressions to their simplest form step-by-step Maths Math Article Trigonometric Functions Value Of Cos 60 Value of cos 60 The value of cos 60 is 1/2. Trigonometry is used to study the measurements of right-angled triangles that deals with the parameters such as length, height and angles of the triangle. It has an enormous application in the real world.Jul 21, 2023 · cos theta cos (60^(@) + theta ) * cos (60^(@) - theta ) = Doubtnut is No.1 Study App and Learning App with Instant Video Solutions for NCERT Class 6, Class 7, Class 8, Class 9, Class 10, Class 11 and Class 12, IIT JEE prep, NEET preparation and CBSE, UP Board, Bihar Board, Rajasthan Board, MP Board, Telangana Board etc Tan 60° = AD/BD = √3 / 1 = √3. We can also write the value of cos 60 degrees in decimal form as: cos 60° = 1/2 = 0.5. Also, we can write the values of sine, cosine and tangent with respect to all the degrees in a table. Let us draw a table with respect to degrees and radians for sine, cosine and tangent functions.Jun 5, 2023 · Firstly, we choose the cosine, i.e., cos (x) \cos(x) cos (x), from the list. Once we have that, we move to the variable field below, which contains the angle. We input 45 ° 45\degree 45° from our problem, and the moment we do that, the cofunction calculator will spit out the answer underneath: the cofunction along with the value. Cos 25 degrees is the value of cosine trigonometric function for an angle equal to 25 degrees. The value of cos 25° is 0.9063 (approx) How to Find Cos 25° in Terms of Other Trigonometric Functions? Using trigonometry formula, the value of cos 25° can be given in terms of other trigonometric functions as: ± √(1-sin²(25°))Maths NCERT Solutions Class 10 Chapter 8 Exercise 8.2 Question 1. Summary: For the following problems: (i) sin 60° cos 30° + sin 30° cos 60° = 1, (ii) 2 tan² 45° + cos² 30° - sin² 60° = 2, (iii) cos 45°/ (sec 30° + cosec 30°) = (3√2 - √6)/8, (iv) (sin 30° + tan 45° - cosec 60°)/ (sec 30° + cos 60° + cot 45°) = (43 - 24√ ...Learn and revise trigonometric ratios of sine, cosine and tangent and calculate angles and lengths in right-angled triangles with GCSE Bitesize AQA Maths. ... [\cos{60} = \frac{1}{2}\]Sep 23, 2019 · In this video, we learn to find the value of cos(-60). Here I have applied cos(-x) = cos(x) identity to find the value of cosine of -60 degree. The URL of th... Mar 18, 2018 · The value is sqrt3/2. You can do each calculation separately and do all the math, or you can recognize the angle difference formula for cosine: cos(A-B)=cosAxxcosB+sinAxxsinB In this case, A is 60^@ and B is 30^@. Free trigonometric simplification calculator - Simplify trigonometric expressions to their simplest form step-by-step Free math problem solver answers your algebra, geometry, trigonometry, calculus, and statistics homework questions with step-by-step explanations, just like a math tutor.Cosine of Complex Angles Specified in Degrees. Create an array of three complex angles and compute the cosine. y = 1×3 complex -1.0002 + 0.0000i 0.7075 - 0.0247i 0.9862 - 0.0091i.Trigonometry Ratios-Sine, Cosine, Tangent. The trigonometric ratios of a triangle are also called the trigonometric functions. Sine, cosine, and tangent are 3 important trigonometric functions and are abbreviated as sin, cos and tan. Let us see how are these ratios or functions, evaluated in case of a right-angled triangle.Maths NCERT Solutions Class 10 Chapter 8 Exercise 8.2 Question 1. Summary: For the following problems: (i) sin 60° cos 30° + sin 30° cos 60° = 1, (ii) 2 tan² 45° + cos² 30° - sin² 60° = 2, (iii) cos 45°/ (sec 30° + cosec 30°) = (3√2 - √6)/8, (iv) (sin 30° + tan 45° - cosec 60°)/ (sec 30° + cos 60° + cot 45°) = (43 - 24√ ...How do you find the exact functional value cos(60˚+45˚) using the cosine sum or difference identity? Trigonometry Trigonometric Identities and Equations Sum and Difference Identities 1 AnswerDefinition of cosine The cosine of an angle is defined as the sine of the complementary angle. The complementary angle equals the given angle subtracted from a right angle, 90°. For instance, if the angle is 30°, then its complement is 60°. Generally, for any angle θ, cos θ = sin (90° – θ).Explanation: Imagine the unit circle: We know that 300∘ is in the fourth quadrant, where cosine is positive. 300∘ has a reference angle of 60∘, since it is 60∘ away from the x -axis. Since cos(60∘) = 1 2, we know that cos(300∘) = 1 2 as well since cos(θ) > 0 in the fourth quadrant. Answer link.Processing ends successfully. Using the trigonometric identity, cos2x = 2cos2x−1 = 1−2sin2x 2cos2x+2 =4cos2x We are looking for an angle that allows for the relationship sinx= cos(2π −x) in the final step. ... You are correct. When k = 0, cos(212π + 72kπ)= cos 212π. When k = 1, cos(212π + 72kπ) =cos 218π. When k = 2, cos(212π ...Sin 60 = √3/2. Sin 90 = 1. Fact: The values sin 30 and cos 60 are equal. Sin 30 = Cos 60 = ½. And. Cosec 30 = 1/Sin 30. Cosec 30 = 1/(½) Cosec 30 = 2. Derivation to Find the Sin 30 value (Geometrically) Let us now calculate the sin 30 value. Consider an equilateral triangle ABC. Since each angle in an equilateral triangle is 60°, therefore What is the cosin of 60? Cos (60) = -0.95241 assuming that angles are measured in radians, as would be done by most mathematicians. If they are measured in degrees, the answer is 0.5.Learn to find the sine, cosine, and tangent of 45-45-90 triangles and also 30-60-90 triangles. Until now, we have used the calculator to evaluate the sine, cosine, and tangent of an angle. However, it is possible to evaluate the trig functions for certain angles without using a calculator.Learn to find the sine, cosine, and tangent of 45-45-90 triangles and also 30-60-90 triangles. Until now, we have used the calculator to evaluate the sine, cosine, and tangent of an angle. However, it is possible to evaluate the trig functions for certain angles without using a calculator.What is tan 30 using the unit circle? tan 30° = 1/√3. To find this answer on the unit circle, we start by finding the sin and cos values as the y-coordinate and x-coordinate, respectively: sin 30° = 1/2 and cos 30° = √3/2. Now use the formula. Recall that tan 30° = sin 30° / cos 30° = (1/2) / (√3/2) = 1/√3, as claimed.これらは sin (θ), cos (θ) または 括弧 を略して sin θ, cos θ と記述される（ θ は対象となる角の大きさ）。. 正弦関数と余弦関数の比を正接関数（タンジェント、tangent）と言い、具体的には以下の式で表される：. 上記3関数の逆数関数を余割関数（コセカント ...
Answer of given expression is sin(-60°) What is Trigonometric functions? Trigonometric functions defined as the functions which show the relationship between angle and sides of a right-angled triangle. Given expression, sin(20°)cos(80°) – cos(20°)sin(80°) ∵ sin(A-B) = sinA.cosB – cosA.sinB. ∴ sin(20°-80°) So, sin(-60°). Ikea ottawa hours
Because cos () is a static method of Math, you always use it as Math.cos (), rather than as a method of a Math object you created ( Math is not a constructor).Because cos () is a static method of Math, you always use it as Math.cos (), rather than as a method of a Math object you created ( Math is not a constructor).For cos 60 degrees, the angle 60° lies between 0° and 90° (First Quadrant). Since cosine function is positive in the first quadrant, thus cos 60° value = 1/2 or 0.5 Since the cosine function is a periodic function, we can represent cos 60° as, cos 60 degrees = cos(60° + n × 360°), n ∈ Z. ⇒ cos 60° = cos 420° = cos 780°, and so on. The proof of the formula is easily found in the web. Starting from cos 60 degree = 1/2, cos30, cos15, cos (15/2), cos (15/4),cos (15/8), cos (15/16) Thus we can calculate value of cos (15/16) degree and may hope it an approximate value of cos 1 degree. Please try it if you have an interest in this method.Cos 300 degrees is the value of cosine trigonometric function for an angle equal to 300 degrees. The value of cos 300° is 1/2 or 0.5 . What is the Value of Cos 300 Degrees in Terms of Sin 300°? Using trigonometric identities, we can write cos 300° in terms of sin 300° as, cos(300°) = √(1 - sin²(300°)). Here, the value of sin 300° is ...Free trigonometric function calculator - evaluate trigonometric functions step-by-step What is quadrantal angle? A Quadrantal angle is an angle that is not in Quadrant I. Consider angle 120. You want to find cos (120) . 120 lies in quadrant II. Also, 120=180-60. So, it is enough to find cos (60) and put the proper sign. cos (60)=1/2. Cosine is negative in quadrant II, Therefore, cos (120) = -1/2.これらは sin (θ), cos (θ) または 括弧 を略して sin θ, cos θ と記述される（ θ は対象となる角の大きさ）。. 正弦関数と余弦関数の比を正接関数（タンジェント、tangent）と言い、具体的には以下の式で表される：. 上記3関数の逆数関数を余割関数（コセカント ...Maths NCERT Solutions Class 10 Chapter 8 Exercise 8.2 Question 1. Summary: For the following problems: (i) sin 60° cos 30° + sin 30° cos 60° = 1, (ii) 2 tan² 45° + cos² 30° - sin² 60° = 2, (iii) cos 45°/ (sec 30° + cosec 30°) = (3√2 - √6)/8, (iv) (sin 30° + tan 45° - cosec 60°)/ (sec 30° + cos 60° + cot 45°) = (43 - 24√ ...The value is sqrt3/2. You can do each calculation separately and do all the math, or you can recognize the angle difference formula for cosine: cos(A-B)=cosAxxcosB+sinAxxsinB In this case, A is 60^@ and B is 30^@.Sin 60° = AD/AB = √3/2. Tan 60° = AD/BD = √3 / 1 = √3. We can also write the value of cos 60 degrees in decimal form as: cos 60° = 1/2 = 0.5. Also, we can write the values of sine, cosine and tangent with respect to all the degrees in a table.cos (135) cos ( 135) Apply the reference angle by finding the angle with equivalent trig values in the first quadrant. Make the expression negative because cosine is negative in the second quadrant. −cos(45) - cos ( 45) The exact value of cos(45) cos ( 45) is √2 2 2 2. − √2 2 - 2 2. The result can be shown in multiple forms..