For each integral below, a function is suggested as its antiderivative. In every case decide, with justification, whether the suggestion is correct. If it is not correct, write a correct antiderivative.
(a) ∫(2x−7)dx; suggestion: x2−7x+C
(b) ∫(ex−sec2x)dx; suggestion: ex−tanx+C
(c) ∫(x1+4x3)dx; suggestion: ln∣x∣+x4+C