Strategy for Integration

Question

Evaluate the integral. (Remember to use absolute values where appropriate. Remember the constant of integration.)

x sec(x) tan(x) dx

Answer 1

By parts: u = x; dv = secxtanxdx; du = dx; v = secx;

xsecxtanxdx = xsecx - ∫secxdx = xsecx - lnIsecx + tanxI + C