**Question:** Find the maximum value and minimum value of each of the following functions. In each case, give the least positive value of x at which they occur.
i. $\displaystyle 9 + \sin(4x-20)^o$

ii. $\displaystyle \frac{30}{11 - 5\cos(\frac{1}{2}x-45)^o}$

**Attempt:**
i. Maximum Value $\displaystyle = 9+1 = 10$ , Minimum Value $\displaystyle = 9-1=8$

ii. Maximum Value = $\displaystyle \frac{30}{11-5\times1} = 5$ , Minimum Value = $\displaystyle \frac{30}{11-5\times-1} = 1.875$

How can I get the values of x in both questions?