- how do I evaluate this integral?

1. Oct 2, 2007

frasifrasi

URGENT - how do I evaluate this integral?

integral from 1 to 4 of sqrt(x)*ln (x) dx

I tried parts but didn't work

Does anyone know?

2. Oct 2, 2007

arildno

Sure it works!
Remember that $$\frac{d}{dx}\frac{2}{3}x^{\frac{3}{2}}=x^{\frac{1}{2}}=\sqrt{x}$$

3. Oct 2, 2007

frasifrasi

The answer is 16/3ln4 - 28/9

WHen i get to int vdu , I have int sqrt(x)*1/x dx, is this right?

Do i just subtract the exponents from here?

4. Oct 2, 2007

yes....