1. 2+2/x^3
2. root(x^2 - 1)+x^2/root(x^2 - 1)
3. x/root(x^2-1)
4. -(root(x)+2)^(-5/3)/(3*root(x))
i cant seem to find the derivative of the following functions, and ive been trying to solve them for close to 4 hours. ive used quotient rule, product rule, chain rule but i still dont get the answers. here they are:
2x^3 - 1 all over x^2
root x(x^3 - x)
root(x-1)(x +1)
((root x) + 2)^-2/3
please help!!
Finding derivatives is completely mechanical.
If you don't get the answers you think you ought to get (e.g. by comparing them with the answers) then:
a) You've done something incorrect when you used the mechanical procedure, or:
b) You *have* got the same result as the answer book, but you haven't completed the algebraic manipulation to prove they are in fact identical.
You've told us what you got for Q1, which shows it's an example of (b). You have not told us what you got for 2, 3 and 4. Before we go any further, that would be a good idea, because then we will know what you have done. Then we will be able to help properly.
Except I'm going off line now because I have a long day tomorrow and it's nearly 11:30 where I am.
You can do them all at WolframAlpha: eg. differentiate Sqrt[x(x^3 - x)] - Wolfram|Alpha
Click on Show steps.
in future, please don't post more than two questions in a thread. Otherwise the thread can get convoluted and difficult to follow. See rule #8: http://www.mathhelpforum.com/math-he...ng-151418.html.
Thread closed.