Integration by parts, Partial fraction expansion, Improper Integrals

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ertagon2
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  1. -
  2. check if right
  3. check if right
  4. Now, 2 seems to be the right answer for A yet when i made x=5 and subtracted new form form the old one I got a difference of ~$\frac{4}{9}$ (should be 0 obviously) I got A=2 B=$\frac{45}{21}$ C=2
  5. How to calculate $\lim_{{x}\to{\infty}}(- e^{-x})$
 
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  • Table of calculus homework questions 2 to 5 with entered answers: integral of x sin 2x from 0 to pi/4 gives 0.25; integral of 3cos^2 x sin x from -pi to pi gives 0; partial fraction value of A is 2; improper integral of x e^(-x) from 0 to infinity gives 1.
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2. Correct
3. Yes, notice that it's an odd function $f(-x)=-f(x)$ so the "areas" cancel out.
4. Might want to check your math here a bit. The answer is correct ($A=2$), but $B=3$ and $C=-2$.
Also, $\lim_{{x}\to{\infty}}(e^{-x})=\lim_{{x}\to{\infty}}1/e^x=0$ since the denominator goes to infinity.
 
Since when is 0.25 a fraction in simplest form?
 
Prove It said:
Since when is 0.25 a fraction in simplest form?

so =$\frac{1}{4}$ ?