- #1
MathematicalPhysicist
Gold Member
- 4,699
- 372
i need to solve/prove the next two integrals:
[tex]\int\frac{dx}{u^2+u+4}[/tex]
and i need to show that:
[tex]\int_{0}^{\pi}\sqrt{1+sinx}dx=4[/tex]
the problem is that i have a clue to substitute u=sinx and then sin(pi)=0=sin0 so the integral should be equal zero, is it not?
ofcourse the integrand becomes: sqrt(1+u)/sqrt(1-u^2)
[tex]\int\frac{dx}{u^2+u+4}[/tex]
and i need to show that:
[tex]\int_{0}^{\pi}\sqrt{1+sinx}dx=4[/tex]
the problem is that i have a clue to substitute u=sinx and then sin(pi)=0=sin0 so the integral should be equal zero, is it not?
ofcourse the integrand becomes: sqrt(1+u)/sqrt(1-u^2)