What is the value of following?

$\rm cot \left[sin^{-1} \frac{3}{5}+cot^{-1}\frac{3}{2} \right]$

Let 4sin² x = 3, where 0 ≤ x ≤ π. What is tan3x equal to?

Let p, q and 3 be respectively the first, third and fifth terms of an AP. Let d be the common difference. If the product (pq) is minimum, then what is the value of d?

Consider the following statements in respect of the roots of the equation x³ - 8 = 0 :

1. The roots are non-collinear.

2. The roots lie on a circle of unit radius.

Which of the above statements is/are correct?