Question

if sin theta = 1/2 , find the value of cos20

it's a optional mathematics Questions please solve him​

Answer 1

Answer:

√3/2

Step-by-step explanation:

p/h=1/2

Using Pythagoras Theorem

b=√3

cos=√3/2

cos20= √3/2*20

= 10√3

Answer 2

Answer:

cos2θ = $\frac{1}{2}$

Step-by-step explanation:

Using the identity

cos2θ = 1 - 2sin²θ

          = 1 - 2($\frac{1}{2}$ )²

          = 1 - 2($\frac{1}{4}$ )

          = 1 - $\frac{1}{2}$

          = $\frac{1}{2}$