Lower level algebra Question Concerning the Solution to a Calculus Problem

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Nevermind I totally got it now, sorry to waste anyones time!
 
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Asphyxiated said:

Homework Statement



\int^{2}_{0} (x+1)^{1/2} dx

The Attempt at a Solution



This problem is very easy to solve, I have no problem with that, but I will list my solution anyway. The problem I am having is finding the solution to the problem that is in the book. Our solutions are the same when approximated to decimals but I have no idea how they got the exact form of the solution, so I am hoping someone can help me here, the problem is solved like so:

\frac {2}{3}(x+1)^{3/2} +C

well that's the indefinite integral anyway, so the solution looks something like this for the definite integral:

\frac {2}{3}(2)^{3/2} - \frac {2}{3}(0)^{3/2}
Your mistake is in the line above. The expression raised to the 3/2 power in your antiderivative is x + 1, not x so both your terms above are incorrect. After evaluating the antiderivative at the two endpoints you should have (2/3)[(2 + 1)^(3/2) - 1^(3/2)].
Asphyxiated said:
and the last portion is going to be zero, so the solution is just:

\frac {2}{3}(2)^{3/2}

right? For exact form anyway? Which could be written this way:

\frac {2}{3} \sqrt{2^{3}}

but what they want is:

\frac {2}{3} (3\sqrt{3}-1)

I know they are the same answers so I just want to know how to get to that answer from the answer I have.

Thanks greatly! And I am sorry if this is really obvious but I can't for the life of me remember this.
 
yeah I seen that, I just did a lot of correcting to that post, so please take a look at it again because it has changed
 
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...

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