261 x 1 dx u x 1 262 263 264 265 266 270 x 1 d u x 1 267 ercis S 2x 3 dx u 2x 3 S 3x 2 dx u 3x 2 the antid rivative using the indicated substitution X dx u x 1 x 1 X 1 x dx u 1 x2 3 x 1 x 2x dx u x 2x 268 2 2x x 32 dr u 2 32 269 cos 0d0 u sine Hint cos 0 1 sin 0 sin 0d0 u cos 0 Hint sin 0 1 cos 0 u