Mathematics
If 20° + x is an acute angle and cos(20° + x) = sin 60°, then find the value of x.
Trigonometrical Ratios
43 Likes
Answer
We know that,
sin 60° = = cos 30°.
Given,
⇒ cos(20° + x) = sin 60°
⇒ cos(20° + x) = cos 30°
⇒ (20° + x) = 30°
⇒ x = 10°.
Hence, x = 10°.
Answered By
19 Likes
Related Questions
If A = 60° and B = 30°, verify that
(i) sin(A + B) = sin A cos B + cos A sin B
(ii) cos(A + B) = cos A cos B - sin A sin B
(iii) sin(A - B) = sin A cos B - cos A sin B
(iv) tan(A - B) =
If 2θ is an acute angle and 2 sin 2θ = , find the value of θ.
If θ is an acute angle and sin θ = cos θ, find the value of θ and hence, find the value of 2 tan2 θ + sin2 θ - 1.
If 3 sin2 θ = and θ is less than 90°, find the value of θ.