Is This Integral Calculation Correct?

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Hi, can anyone help please as I'm getting tied up in knots...

Homework Statement



Integrate (5x^2 + √x - 4/x^2) dx

Homework Equations



I think this is differentiating by parts...

The Attempt at a Solution



So far I've got to: 5x^3 / 3 + 2x^3/2 / 3 + 4 / x +c

I can't think how I can make it any tidier so any tips would be really appreciated!
 
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Two questions for you:

(1) What is:
\int( f(x) + g(x)) dx
(2) What is:
\int x^k dx
 
Question (3): What is 'differentiating by parts'?
 
lemon26 said:
Hi, can anyone help please as I'm getting tied up in knots...

Homework Statement



Integrate (5x^2 + √x - 4/x^2) dx

Homework Equations



I think this is differentiating by parts...

The Attempt at a Solution



So far I've got to: 5x^3 / 3 + 2x^3/2 / 3 + 4 / x +c

I can't think how I can make it any tidier so any tips would be really appreciated!

Because you do not use parentheses, I cannot figure out whether you mean
(1) \; \int \left(5 x^2 + \sqrt{x} - \frac{4}{x^2} \right) \, dx \leftarrow \text{ what you wrote}
or
(2) \; \int \left( 5 x^2 + \sqrt{x - \frac{4}{x^2}} \right) \, dx
or
(3) \;\int \left(5 x^2 - \frac{ \sqrt{x-4}}{x^2} \right)\, dx
or
(4) \;\int \left(5 x^2 - \sqrt{ \frac{x-4}{x^2} } \right)\, dx
 
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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