if cos (40°-X)=30sin find the value of X

Asked by lavanyasureshkumar | 24th Aug, 2020, 04:02: PM

Expert Answer:

Question: cos (40°-X)=sin30°
 
 We know that, sin(90° - θ) = cosθ

∴sin30° = sin(90°-60°) =cos60°
∵cos(40°+x) = sin30°... given
⇒cos(40°+x) = cos60°
⇒40°+x = 60°
⇒ x = 20°

Answered by Yasmeen Khan | 25th Aug, 2020, 12:25: PM