Plz do show all steps

1. Find the partial fraction decomposition for the following rational functions: 3x+7 x2-1 6x2-x-1 (b) x3-x x*+5x3+x-15 (c) x2+5x 2. Evaluate each of the following integrals, using a trigonometric substitution. Do not forget the back substitution. Solving using other methods is not acceptable. Solving using a formula is not acceptable. (a) SV1 - 36x2 dx V25-x2 (b) dx (c) dx x2+49 3. Evaluate each of the following integrals: (a) So cos3 (5x) dx (b) S sec3 (5x)tan? (5x) dx (c ) sin 6x sin 2xdx