Here are some properties of exponents that you'll need:
- xa*xb = xa+b
- 1/xa = x-a
91/4/93/4
= 91/4*9-3/4 [Property 2]
= 91/4-3/4 [Property 1]
= 9-1/2 [1/4 - 3/4 = -2/4 = -1/2]
= 1/91/2 [Property 2]
= 1/3 [91/2 = (32)1/2 = 3]