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## #1 2006-01-22 07:30:12

suetonius
Member
Registered: 2006-01-22
Posts: 1

### anitderivative of 1/sqrt(x)

Can anybody help me find the antiderivative of 1/sqrt(x)?

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## #2 2006-01-22 09:33:16

irspow
Member
Registered: 2005-11-24
Posts: 457

### Re: anitderivative of 1/sqrt(x)

The derivative of any fractional function:

f(x) = f(g)/f(h),  f'(x) = [ f'(g)f(h) - f(g)f'(h) ] / (f(h))²

f(g) = 1,  f(h) = √x,  f'(g) = 0,  f'(h) = 1/(2√x)

So, using the formula for differentiating fractions above, this all becomes;

[ 0(√x) - 1(1/(2√x))] / (√x)²;

This equals;

-1/(2x√x) = (-1/2)x^(-3/2)

Note that this type of discussion belongs in the "HELP ME!" section.  Please post your math questions there in the future.

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## #3 2006-01-22 12:58:45

ryos
Member
Registered: 2005-08-04
Posts: 394

### Re: anitderivative of 1/sqrt(x)

He was asking for the antiderivative, AKA the integral.

1/√x can be rewritten as ½x^-½. This can be integrated simply by the power rule for integration: ∫½x^-½dx = x^½ or √x.

Last edited by ryos (2006-01-22 13:01:30)

El que pega primero pega dos veces.

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## #4 2006-01-22 15:28:42

irspow
Member
Registered: 2005-11-24
Posts: 457

### Re: anitderivative of 1/sqrt(x)

Haha,  I guess that I was thrown off by this being posted in the wrong section.  It seems fitting that a wrong answer was given for a question posted in the wrong place.

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## #5 2006-01-22 18:48:31

justlookingforthemoment
Moderator
Registered: 2005-05-26
Posts: 2,161

### Re: anitderivative of 1/sqrt(x)

Well, I was going to move it, but then I wasn't sure whether suetonius would be able to find it again.

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## #6 2006-01-23 03:31:05

Ricky
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Registered: 2005-12-04
Posts: 3,791