Question

If sin ø – cos ø = 0, then the value of (sin2ø + cos4ø) is

(a) 1 (b) 3/4 (c)1/2 (d) 1/4​

Answer 1

Answer:

Answer = 3/4

Step-by-step explanation:

sin ø = cos ø

ø = 45°

= sin²45 + cos⁴45

= (1/√2)² + (1/√2)⁴

= 1/2 + 1/4

= 2+1/4

= 3/4

Answer 2

Given,

sin θ - cos θ = 0

sin θ = cos θ when θ = π/4, 5π/4 ....

take θ = π/4

sin 2θ = sin π/2 = 1

cos 4θ = cos π = -1

sin 2θ + cos 4θ = 1 - 1 = 0

At θ = 5π/4

sin 2θ = sin 5π/2 = 1

co 4θ = cos 5π = -1

sin 2θ + cos 4θ = 1 - 1 = 0

Whatever the value of θ, sin 2θ + cos 4θ = 0 when sinθ = cosθ

I hope, none of the options are correct