Let f be the continuous function defined on [−1,8] whose graph, consisting of two line segments, is shown above. Let g and h be the functions defined by g(x)=x2−x+3−−−−−−−−−√ and h(x)=5ex−9sinx.

(a) The function k is defined by k(x)=f(x)g(x). Find k′(0).