Question

24. sinº + cos6 O is equal to
(b) (sin + cos2 02
3
(a) 3 sind o cos26
3 sin cos e
(c)
cosec O seco
(d) 1-3 sin? 0 cos20​

Answer 1

Step-by-step explanation:

sin

6

θ+cos

6

θ+3sin

2

θcos

2

θ

⇒LHS=(sin

2

θ)

3

+(cos

2

θ)

3

+3sin

2

θcos

2

θ

Using, [a

3

+b

3

=(a+b)

3

−3ab(a+b)]

⇒LHS=(sin

2

θ+cos

2

θ)

3

−3sin

2

θcos

2

θ(sin

2

θ+cos

2

θ)

3

+3sin

2

θcos

2

θ

⇒LHS=1−3sin

2

θcos

2

θ+3sin

2

θcos

2

θ=1=RHS