I can't do these problems on trigonometry, can someone help me on these please ?
Show that for all x which is an element of R,
cos x = 1- (1/2!)x^2 + (1/4!)x^2...and sin x = x - (1/3!)x^3 + (1/5!)x^5...
(a) To do this, let C(x) and S(x) denote the sums of the two series. Verify that...