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dths1980
Jun 23, 2008, 09:25 AM
can someone help please

f(x) = x^2/(x^2+1)^1/2

ebaines
Jun 23, 2008, 10:01 AM
The derivative of a quotient is found using the following rule:

For

f(x) = \frac {g(x)} {h(x)}

The derivative f'(x) is found by:


f'(x) = \frac{ h(x)g'(x)-g(x)h'(x)} {([h(x)]^2}


For your problem:

g(x) = x^2 and h(x) = \sqrt {x^2+1}.

Post back if you have more questions on this.

galactus
Jun 24, 2008, 05:10 AM
You can also use the product rule on this by writinf it as

\underbrace{x^{2}}_{\text{f(x)}}\overbrace{(x^{2}+ 1)^{\frac{-1}{2}}}^{\text{g(x)}}

The product rule is f(x)g'(x)+g(x)f'(x)

I always thought it was easier to use the product rule if one can.

Unknown008
Jun 24, 2008, 05:27 AM
Yup, its shorter and does not require the squared of the second term.