2nd DerivativeDate: Mon, 21 Nov 94 10:49:33 AST From: "Jim Mullen" Subject: math problem I am a grade twelve student taking calculus and was wondering if you could help me with this problem. y=2x(6x+5)exp4 solve to the second derivative Any help will be greatly appreciated! Date: Mon, 21 Nov 1994 10:47:55 -0500 (EST) From: Dr. Ken Subject: Re: math problem Hello there! I think the way that we would write your function is 2x(6x+5)^4. Is that right? It looks like we're going to have to use the product rule a couple of times to take two derivatives of your function. Have you seen the product rule before? Here it is: [f(x)g(x)]' = f'(x)g(x) + f(x)g'(x). So here's how it applies in our situation: we take the derivative of 2x, mulitiply that by (6x+5)^4, and then add that to 2x times the derivative of (6x+5)^4. So we get 2(6x+5)^4 + 48x(6x+5)^3 as our first derivative. Do you see why? The next step, finding the second derivative, will be very similar, and I'll let you try it yourself. Write back if you have more questions! -Ken "Dr." Math |
Search the Dr. Math Library: |
[Privacy Policy] [Terms of Use]
Ask Dr. Math^{TM}
© 1994- The Math Forum at NCTM. All rights reserved.
http://mathforum.org/dr.math/