Find the indefinite integral of the function 4x7 - x + 4x 2x6 (Hint: it may be helpful to simplify f(x) first.) f(x) = = Use integration by substitution to find the indefinite integral in part (a) and to evaluate (to 2 d.p.) the definite integral in part (b). In part (b), you may use the approximation e 2.71828 in the final evaluation. 328 +225 29 +26 et elet) dt (a) S (b) dz (a) Use integration by substitution to find the indefinite integral x5 x dx. (Hint: it may help to factorise the numerator.) (b) Use integration by parts twice to find the indefinite integral [(y + 1)e-dy.