Question

cos⁴ theta - sin⁴ theta = ..............​

Answer 1

Answer:

hii

Step-by-step explanation:

sin

4

θ+cos

4

θ=(sin

2

θ+cos

2

θ)

2

−2sin

2

θcos

2

θ

=1−

2

1

(sin

2

2θ)

2

[∵cos

2

θ+sin

2

θ=1andminimumvalueofsin

2

2θis0]

sin

4

θ+cos

4

θ

=1−0

sin

4

θ+cos

4

θ = 1