Approximate the value of the given integral by completing parts (a) and (b) below (a) Use the trapezoidal rule, using n = 4. (b) Check by direct integration. [ex ? dx 0 (a) Use the trapezoidal rule to approximate the integral. 6x dxo 0 Type an integer or a decimal.) (b) Find the exact value of the integral by integration. N 6x2dx = (Type an integer or decimal rounded to two decimal places as needed.)