Page:Elementary algebra (1896).djvu/417

399 Rh To find the coefficient of x^r;

(1) If r is even, the coefficient of x^r in the second series is 4(-1)^{r 2}; therefore in the expansion the coefficient of x^r is 3+4(-1)^{r 2}. (2) If r is odd, the coefficient of x^r in the second series is -3(-1)^, and the required coefficient is 3(-1)^- 3.

EXAMPLES XLII. e.

Resolve into partial fractions :

Find the general term of the following expressions when expanded in ascending powers of x.