Integrate the following tt4+2dt?

2 Answers
Feb 19, 2017

122tan1(t22)+C

Explanation:

Let t2=2tanθ. This implies that 2tdt=2sec2θdθ. Then:

I=122tdt(t2)2+2=122sec2θdθ(2tanθ)2+2

Continuing on and using tan2θ+1=sec2θ:

I=12sec2θ2tan2θ+2dθ=122sec2θsec2θdθ=122dθ

We're working in terms of θ:

I=122θ+C

From t2=2tanθ we see that θ=tan1(t22):

I=122tan1(t22)+C

I solved this way:
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