Originally Posted by

**cliste09** hey this is an exam question i got stuck on,(im prob going to be posting a few of these just to let you know in advance lol) :

differentiate (x^2 + 9) (4x^3 + 5) with respect to x,

i know its where u have to use the dy over dx formula but i just have a hard time with this one and many others,so an easy explanation would be greatly appreciated as i am barely hanging on by a thread in ordinary level maths, the highest grade i have ever gotten is a C lol thanks!!

the correct answer is :20x^4 + 108x^2 + 10x