It's mostly just an algebra problem in the numerator. Notice that
so:
If the terms are throwing you off, you can use instead. This is actually more common notation anyway.
Does this help?
Hi! I'm new to Math Help Forums, so you'll have to forgive me if I don't do things correctly. I'm not quite sure how to post math icons either =/
So, I just have a basic difference quotient problem that was actually included in my review packet for the beginning of calculus one.
Question:
Evaluate the function at the given value of the independent variable.
F(x) = x^3
f(x+deltax)-f(x)/delta x
I got as far as plugging it in:
(x+delta x)^3-x^2/delta x
And, I know I'm supposed to simplify things out to get rid of the delta x on the bottom. I tried multiplying out the top and I got [x^2+x(delta x) +x(delta x) + (delta x)^2][x+delta x]/delta x. I'm not entirely sure if that's right, because the delta x's kind of confuse me. I wasn't quite sure how to continue.
Thanks!
EDIT: I forgot to mention! The back of the book states that the answer is 3x^2 + 3x(delta x)+(delta x)^2, where delta x does not equal zero. Thanks again!