if that's true, by using and , this simplifies to
now do a substitution. let and the rest should be simple
2. integral (b = 1, a = 0) x(sqrt (x^2 + 4)) dx
you can do a trig substitution here,3. integral (du)/(u(sqrt(5-u^2)))
yes, that can work. this becomes4 integral (dt)/(sqrt(t^2 -6t +13))
for this one, i think we are supposed to complete the square and then evaluate the integral..
now do a trig substitution.