SECTION 2.-Integration of Circular Functions. 65.] Integration of the fundamental circular functions. 66.] And all the preceding formulæ are of course true when for x any function of x, say f(x), is substituted, provided that do is replaced by f'(x) dx. Thus = [sin(x3) x2 dx = {} [sin(x3) d.æ3 3 cos (mx2+nx+p) (2mx+n) dx = sin (mx2+nx+p). |