Option-direct substitution-simplify a complex fraction-multiply by a conjugate-factor and cancel

Have a look at the "Problem-Solving Strategy" directly before Example 2.17. Use the Problem-Solving Strategy (and other information in Section 2.3) to determine the most appropriate technique for evaluating each of the following limits: a) lim V3x+16-5 [ Select ] X-3 x-3 b) lim 7th 7 [ Select ] h-0 h c) lim x2-2x-3 [ Select ] X--1 x2+2x+1 d) lim x -2x-3 [ Select ] X-2 x+5x+6 e) lim [ Select ] x x+0 x2 +x