How Can I Solve This Integral Using Trigonometric Substitution?

[sania16]

Homework Statement

$$\int1/\sqrt{(4+9x^2)^3}dx$$




3. The Attempt at a Solution :

i think i do all options that i now, but i cannt to make a solution of this, (the way)? may be anybody can help me,

 

[pellman]

You can get the answer here: http://integrals.wolfram.com/index.jsp

Enter 1/(Sqrt((4+9*x*x)^3))

Maybe once you have the answer it will give you some ideas about how to solve it.

If you still need help, come back and let us know.

 

[sania16]

eeeeeeeeemmmh thnks, the answer i know, and in others sites,i gave the same answer,

but i want to see the way... :(((((((((((

 

[tiny-tim]

Welcome to PF!

Hi sania16! Welcome to PF!

(have a square-root: √ and an integral: ∫ and try using the X² tag just above the Reply box )

eeeeeeeeemmmh thnks, the answer i know, and in others sites,i gave the same answer,

but i want to see the way... :(((((((((((

Quite right!

Hint: for √(a ± bx²), always try a trig substitution first. ​

 

[sania16]

yes you right ! thank you.

i change 3x=2tg(t), and everything being cool!

thanks to all of you!

p.s: how much time i spend on this... :(