4. Verify that L' Hospital's rule can be used to evaluate the following limits. Then use it to evaluate them. (Note: no marks will be awarded if limits are calculated by any other method). (a) lim Vath - Vx h-+0 h r-p-r+l (b) lim 2x5 + 3.r4 - 313 - x2 + 3x - 1