Simple integration for an area problem

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Homework Statement


ieKweIK.png

Homework Equations


Integration of graph is the area.

The Attempt at a Solution


KpUfOnC.jpg

I don't think my way should have any problem in it, but I can't get the right answer.
Are there any careless mistakes in it? Or any other problems?
And how is the true answer get? And what is the answer?
Thank you very much
 
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Problems involving integration should NOT be posted in the Precalc section.
Thread moved.
 
yecko said:

Homework Statement


ieKweIK.png

Homework Equations


Integration of graph is the area.

The Attempt at a Solution


KpUfOnC.jpg

I don't think my way should have any problem in it, but I can't get the right answer.
Are there any careless mistakes in it? Or any other problems?
And how is the true answer get? And what is the answer?
Thank you very much

I refuse to lie sideways to read your work. Anyway, the preferred method in this forum is for you to type out your solution; some people will look at photos of solutions, but only if they are properly oriented.
 
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yecko said:
http://i.imgur.com/WvL8be9.jpg
WvL8be9.jpg

sorry for the problems. i didn't aware of them. hope you may help with this. thank you

Your total area result is correct. Computing A2 instead of A1 seems easier, since you do not need to break up the integration region into two parts: you just have ##A_2 = \int_0^{x_m} (4x - 5 x^2 - mx) \, dx,## where ##x_m## is the positive intersection point. From the requirement ##A_2 = (1/2) A## I get the equation
$$ -\frac{1}{150} m^3+ \frac{2}{25} m^2-\frac{8}{25} m+ \frac{32}{75} = \frac{16}{75},$$
leading to a much different ##m## than yours.
 
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There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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