EXAMPLE 3 Find 3 _ 5x2 dx. SOLUTION Let u = 3 - 5x2. Then du = dx, so x dx = du and V3 - 5 x2 dx = 14 - 3 12 du ( 2Vu) + c + C (in terms of x). Evaluate the integral by making the given substitution. (Use C for the constant of integration.) e - 4X dx , u = - 4X Evaluate the integral by making the given substitution. (Use C for the constant of integration.) cost1 0 sin e de , u = cos Tutorial Exercise Evaluate the indefinite integral. v10 + ex dx Step We must decide what to choose for u. If u = f(x), then du = f '(x) dx, and so it is helpful to look for some expression in ex v 10 + ex dx for which the derivative is also present. We see that 10 + ex is part of this integral, and the derivative of 10 + ex is which is also present. Submit Skip (you cannot come back)