sin (21 ∘) = 10 5 Step 5: Simplify the Calculation. Simplify the fraction: sin (21 ∘) = 2 1 Therefore, the sine of 21 degrees is equal to 1/2. Recap. In this lesson, we learned how to find the sine of 21 degrees using the trigonometric function formula.

2018年3月13日 · Given : sin 21° Solution : To show how Cos 69 ° = Sin 21 ° we will use sine and cosine trigonometric identity . i.e.** Cos (90 °-x) = Sin x ** ---(A) We are given Sin 21 ° So, putting x =21 ° in (A) We are getting : Cos(90 °-21 °) = Sin 21 ° ⇒**Cos 69 ° = Sin 21 ° ** Hence it is shown that Cos 69 ° = Sin 21 °

2025年1月31日 · The equivalent positive angle for − 21 0 ∘ is 36 0 ∘ − 21 0 ∘ = 15 0 ∘. However, from trigonometric identity sin (− θ) = − sin (θ), we have sin − 21 0 ∘ = − sin 21 0 ∘. Co-terminal angle for 21 0 ∘ is sin 15 0 ∘, which equals sin 3 0 ∘ = 0.5, but with a negative sign here, giving − 0.5. Therefore, sin − 21 0 ...

2021年7月14日 · Option B: sin R = 20 21 Again, this cannot be true for the same reason; it is also greater than 1. Option C: sin R = 29 20 This value is valid since it is between 0 and 1. We can assume this describes a scenario where the opposite side is 20, and the hypotenuse is 29. Option D: sin R = 29 21 This value is also valid since it lies between 0 and 1.

for positive acute angles A and B, it is known that sin A = 40/41 and tan B = 20/21. find the value of sin(A+B) in simplest form Answer:sin(A+B) = sinAcosB+sinBcosA if cosA = 9/41 then sinA =j40/41 It's a 9-40-41 right triangle

2025年1月24日 · To find sin 4 21 π , we need to simplify the angle first. 1. Convert the angle to a standard range: - The sine function has a periodicity of 2 π. Therefore, we can reduce any angle by subtracting multiples of 2 π until the angle is within the interval [0, 2 π). 2. Simplify 4 21 π : - Calculate how many full circles (2 π) fit into 4 21 π .

2024年7月27日 · To determine the length of the blade of the windmill using the equation h = 7 sin (21 π t) + 28, we can analyze the components of the sine function in the equation step-by-step. The equation can be described in the form: h = A sin (Bt) + C where: A is the amplitude of the sine function. B determines the period of the sine function.

2023年7月19日 · Given that sin 69°=sin (90°-21°), apply the difference identity to find the following: sin 69° A. cos 1110 B. CSC 21° C. csc 111° D. cos 21°

2023年9月17日 · For example, if d = 1, then for 76, we would have tan (sin (21 x)). For 78 , if x = 0.5 , substituting into 1 − x 2 gives us 1 − ( 0.5 ) 2 = 0.75 . The simplification of sin 2 ( arccos ( x )) = 1 − x 2 is based on the fundamental Pythagorean identity in trigonometry, where knowing that the square of sine plus the square of cosine equals ...

Given: QR = 36, PR = 45, PQ = 21. Find: sin θ = 45 21 . (Note: The original question seems to be missing context. The expression sin θ = 45 21 suggests a right triangle scenario where PQ might be the opposite side, and PR is the hypotenuse. Make sure the context is clear or specify the missing information for a complete question.)