Question

integral of x*(x^2+2x+4)^1/2

Answer 1

Use a u-substitution for the portion of the integrand inside the parens. I think you'll get good results.

Answer 2

Trig sub, complete the square then u sub then trig sub, evaluate then back sub

Answer 3

i've got some of the answer getting stumped on integral of sec^3(x)

Answer 4

Yeah, it's looking like a right mess. I missread the square root part (didn't see the 2x term) so a nice u-sub this isnt.

Answer 5

i completed the square & then u -sub

Answer 6

i went to wolfram & am at the 8th integral down

Answer 7

When you do sec^3(x) you have to break it up to sec^2(x)sec(x)=(1+tan^2(x))sec(x) distribute and evaluate, then you have to use the fact that the integrand has the original integral in it, add it/subtract it over then simplify. Its a crafty one.

Answer 8

http://www.wolframalpha.com/input/?i=integral+of+sec^3(x)dx

Answer 9

Or use a reduction formula lol. I thought wolfram had it worked out the other way :P