If sin2x = cos(2x - 40°) where 2x is an acute angle find the value of 2x.
Answer & explanation
Correct answer: option 3
We know that if sinA = cosB, then A + B = 90°
ATQ,
sin2x = cos(2x-30°)
⇒ 2x + 2x - 30° = 90°
⇒ 4x = 120°
⇒ 2x = 60°
If sin2x = cos(2x - 40°) where 2x is an acute angle find the value of 2x.
Correct answer: option 3
We know that if sinA = cosB, then A + B = 90°
ATQ,
sin2x = cos(2x-30°)
⇒ 2x + 2x - 30° = 90°
⇒ 4x = 120°
⇒ 2x = 60°