Question

If sinθ – cosθ = 0, then the value of (sin4 θ + cos4θ) is (A) 1 (B) 3 4 (C) 1 2 (D) 1 4

Answer 1

Answer:

Step-by-step explanation:

Answer 2

Answer:

Step-by-step explanation:

sinθ-cosθ = 0

sinθ= cosθ

sinθ/cosθ = 1

tanθ = 1

Bu tan45 = 1

So,

tanθ=tan45

θ = 45°

sin45 = 1/√2 cos45 = 1/√2

sin⁴θ+cos⁴θ = (1/√2)⁴+(1/√2)⁴

= 1/4+1/4 = 2/4 = 1/2 = 0.5