Question

The solution set of equation sin⁴x = 1 + cos⁶x is

• A. 2np + $\frac{\pi}{2}$ (n Ī I)
• B. 2np (n Ī I)
• C. np + $\frac{\pi}{2}$ (n Ī I)
• D. No solution

Answer 1

Answer: (C)

np + $\frac{\pi}{2}$ (n Ī I)

Answer 2

sin⁴x = 1 + cos⁶x

Ž \L.H.S £ 1 & R.H.S ³ 1

\ L.H.S = R.H.S = 1so sin⁴x = 1 Ž sin²x = 1

Ž x = np ± p/2, n Ī I & cos⁶x = 0

Ž cos²x =0 Ž x = np ± p/2