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Integration Problem

Date: 22 Feb 1995 17:31:27 -0500
From: Anonymous
Subject: Re: math problem

Hello there!

How do you integrate the function:
                              (tan2x)^3 dx, in terms of x?
Thank you,
   confused with calculus

Date: 22 Feb 1995 17:31:27 -0500
From: Dr. Ken
Subject: Re: math problem

I'll give you a hint, and if you're still confused, come back and I'll try
to explain it in more detail.

You've got (Tan2x)^3, which splits into (Tan2x)(Tan2x)^2.  Now 
remember the formula Tan^2 u + 1 = Sec^2 u, and use it to turn your 
integrand into (Tan2x)((Sec2x)^2 - 1).  Distribute the Tan2x to get 
Tan2x(Sec2x)^2 - Tan2x.  Now can you do the problem?

-Ken "Dr." Math
Associated Topics:
High School Calculus

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