Question

if cos 20=sin 40, where 20 and 40 are acute angles, find the value of theta

Answer 1

Answer:

it is u answer .

please mark as brainlist.

Answer 2

Question

If cos 2θ = sin 4θ, where 2θ and 4θ are acute angles, find the value of θ.

Solution

A/q,

cos 2θ = sin 4θ

⇒sin (90 - 2θ) = sin 4θ

As sin(90 - θ) = cosθ and vice-versa.

⇒ 90 - 2θ = 4θ

Same bases are cancelled

⇒ 90 = 4θ + 2θ

⇒ 96 = 6θ

⇒ θ = 90/6

⇒ θ = 15°