Differentiate: f(x) = (x)(√(x^2+5))

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Nawz
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Homework Statement



Differentiate.

f(x) = (x) (square root of (x2+5))

Homework Equations





The Attempt at a Solution



f(x) = (x) (square root of (x2+5))

=(x)(x2+5)1/2

f'(x)=(x)1/2(x2+5)-1/2(2x)+(1)(x2+5)

=x3/(x2+5)1/2+(x2+5)1/2

I'm having problems simplifying. The answer in the back of the book is 2x^2 + 5 / Square root of x^2+5..
 
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Nawz said:

Homework Statement



Differentiate.

f(x) = (x) (square root of (x2+5))

Homework Equations





The Attempt at a Solution



f(x) = (x) (square root of (x2+5))

=(x)(x2+5)1/2

f'(x)=(x)1/2(x2+5)-1/2(2x)+(1)(x2+5)
The above is correct, but you made a mistake in the next line.
Nawz said:
=x3/(x2+5)1/2+(x2+5)1/2
This should be [tex]\frac{x^2}{(x^2 + 5)^{1/2}} + (x^2 + 5)^{1/2}[/tex]

You can take a factor of 1/(x2 + 5)1/2 from both terms above.
Nawz said:
I'm having problems simplifying. The answer in the back of the book is 2x^2 + 5 / Square root of x^2+5..