(4 points) Prove the product rule for three functions. That is find ddx[f(x)g(x)h(x)](Hint: group two of the three functions together and use the product rule twice).(4 points) For the next two questions, recall that an odd function satisfies the property -f(-x)=f(x) and an even function satisfies the property f(-x)=f(x)a. Show that if a function is odd then its derivative is even.b. Show that if a function is even then its derivative is odd.