Solution to Incorrect Homework Equation

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Homework Statement



so I did

Homework Equations



s=∫ba√(1+[f'(x)]2dx

The Attempt at a Solution


y=2/3x3/2+7
y'=x1/2 0≤x≤1
=∫6√(1+(x1/2)2)dx
=[2/3(1+x)3/2]7

my answer came out wrong
 

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chapsticks said:

Homework Statement



so I did

Homework Equations



s=∫ba√(1+[f'(x)]2dx

The Attempt at a Solution


y=2/3x3/2+7
y'=x1/2 0≤x≤1
Why do you have this inequality?
chapsticks said:
=∫6√(1+(x1/2)2)dx
=[2/3(1+x)3/2]7

my answer came out wrong
What is that 7 doing?
 
I saw it in an example for the inequality.. The 7 is for the a & b part I don't know how to place the 0 on the bottom.
 
chapsticks said:
I saw it in an example for the inequality.. The 7 is for the a & b part I don't know how to place the 0 on the bottom.
Your inequality is saying that the interval is [0, 1]. It's actually [0, 6].

Here's how your integral looks using LaTeX.
\int_0^6 \sqrt{1+x}~dx

Here's how to write that integral in LaTeX.

[ tex]\int_0^6 \sqrt{1+x}~dx[ /tex]

(The extra spaces in the tex and /tex tags prevent the browser from rendering the code inside.)

Here's the antiderivative with limits of integration shown.
\left. \frac{2}{3}(1 + x)^{3/2}\right|_0^6

The LaTeX for that.
[ tex]\left. \frac{2}{3}(1 + x)^{3/2}\right|_0^6[ /tex]
 
I got it correct :))
 

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Good to know. That's what I got, too.
 
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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