Evaluate the definite integral using its definition Evaluate the definite integral using its definition: 3 (3x + 2x 1)dx. Use the following form of the definition of the integral to evaluate the integral: Theorem: If f is integrable on [a, b], then b [ f(x) dx = lim f(x) Ax n where Ax = (b a)/n and x = a +ix. n i=1