I have really been struggling to do this integral. Please help! again, it's: Integral of: sec(6x)tan(6x) Thanks!
Follow Math Help Forum on Facebook and Google+
Originally Posted by sj9110 I have really been struggling to do this integral. Please help! again, it's: Integral of: sec(6x)tan(6x) Thanks! Try this substitution $\displaystyle u=6x$.
actually i just realized the whole thing is in parentheses if that makes a difference intsec(6x)tan(6x))dx
Originally Posted by sj9110 actually i just realized the whole thing is in parentheses if that makes a difference intsec(6x)tan(6x))dx Did you try what I said?
yes, but i'm stuck at (1/6) integral [sec(u)tan(u)]du
Originally Posted by sj9110 yes, but i'm stuck at (1/6) integral [sec(u)tan(u)]du What is the derivative of $\displaystyle sec(u)$ ?
sec(x)tan(x) ...but i don't see how to incorporate it all.
If the derivative of $\displaystyle g(x)$ is $\displaystyle f(x),$ it means that the integral of $\displaystyle f(x)$ is $\displaystyle g(x)$ plus a constant.
Originally Posted by sj9110 sec(x)tan(x) ...but i don't see how to incorporate it all. No. Its sec(u)tan(u). If the derivative of sec(u) is sec(u)tan(u) .. then what is the integral of sec(u)tan(u) ? Excause me, Do you know the Fundamental Theorem of Calculus ?
i got an answer of (1/6)sec(6x) + c ... is this right?
Originally Posted by sj9110 i got an answer of (1/6)sec(6x) + c ... is this right? Yes. You are correct.
Originally Posted by General No. Its sec(u)tan(u). If the derivative of sec(u) is sec(u)tan(u) .. then what is the integral of sec(u)tan(u) ? Excause me, Do you know the Fundamental Theorem of Calculus ? It's been a year since I took calculus 1 and 2, so I am pretty rusty.
Originally Posted by General Yes. You are correct. great!..i was just getting a bit confused with all the substitution and stuff. Thanks for your help!
View Tag Cloud