Question

Help please I am lost

Answer 1

G'(x) = 1 × g(x) × f(x) + g'(x) × x × f(x) + f'(x) × x × g(x)

G'(x) = g(x).f(x) + x.f'(x).g(x) + x.g'(x).f(x)

Thus ;

G'(3) = g(3).f(3) + 3f'(3).g(3) + 3g'(3).f(3)

G'(3) = 13×9 + 3×( - 11 )×13 + 3×( - 5 )×9

G'(3) = 117 + ( - 429 ) + ( - 135 )

G'(3) = 117 - 135 - 429

G'(3) = - 18 - 429

G'(3) = - 447