integration problem

[katyt]

i need help finding this integral please!

the integral of (x^2)/(25+x^2)dx

thank you for any help!

Katy

 

[Guest]

(x^2)/(25+x^2)dx

rewrite this as
(x^2) . (25 +x^2)^(-1) dx

then apply the u.v method ie u= x^2 v =(25+x^2)^(-1)

have a go now.

 

[Guest]

sorry had a mind blank --doing to may dy/dx problems in a row --will get back to you.

 

[tkhunny]

Looks like a job for long division and a tangent substitution, to me.

x²/(25+x²) = 1 - 25/(25+x²)

 

[katyt]

more help?

ok so can anyone help me with the tan substitution? i just learned it and i'm having some trouble

 

[katyt]

nevermind i figured it out!