Calculus
posted by Z32 on .
Evaluate the definite integral
The S thingy has 1 at the bottom and 9 at the top. 4x^2+5 divided by the sqrt of x.

The S thingy is called the integral sign.
The number at the bottom (1) is the lower limit of a definite integral, and the top number (9) is the upper limit of integration.
The expression to be evaluated probably looks similar to this:
I = âˆ«_{1}^{9} (4*x^2+5)/sqrt(x) dx
If you use the substitution
u=sqrt(x), then
du=(1/2)*dx/sqrt(x)
Substituting the limits and the variables involving x, we get
I= âˆ«_{1}^{9} (4*x^2+5)/sqrt(x) dx
= âˆ«_{sqrt(x)}^{sqrt(9)} (4u^4+5)*2 du
= âˆ«_{sqrt(x)}^{sqrt(9)} (4u^4+5)*2 du
Continuing the integration and evaluate the integral according to the integration limits, we should obtain 2036/5 as the numerical answer.
Post if you need more details. 
Thanks for the help!

In case it confused you, the substituted lower limit should have read sqrt(1).