Patrick B. answered 02/14/21
Math and computer tutor/teacher
IBP
U = x dV = g'(x)
dU = dx V = g(x)
the integral is
x g(x) - integral [ g(x) dx]
limit of x g(x) as x->4 is 4 * 6 = 24
limit of x g(x) as x->1 is 1 * -3 = -3
definite integral is given to be -8
therefore, [24 - -3] - -8
=27 - -8
= 35