Question

Solve problems on Trigonometric ratios and identities

Question 9 please.

Answer 1

Answer:

Range of f(θ) is = [ 3/4 , 1 ].

Step-by-step explanation:

Find the first two derivatives of f(θ) wrt θ.  

Then find values of θ when f '(θ) = 0.

    For f ''(θ) for those values:

        If f ''(θ) is negative then f(θ) value is a local maximum.

        If f ''(θ) is positive then f(θ) is a local minimum.

The detailed answer is given in the enclosed picture.

Answer 2

Answer:

Step-by-step explanation:

Find the first two derivatives of f(θ) wrt θ.  

Then find values of θ when f '(θ) = 0.

    For f ''(θ) for those values:

        If f ''(θ) is negative then f(θ) value is a local maximum.

        If f ''(θ) is positive then f(θ) is a local minimum.