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"(i) Use the substitution x = 2 - cosθ to evaluate the integral
(ii) Show that, for a < b,
I have done the first part and got
which is correct (according to WolframAlpha). But the second part of the question confuses me. I have done this:
Let x = (b - a) - cosθ, then dx = sinθdθ
and I have ended up with this:
but I do not know where to go from here. Help would be appreciated.
Hmm, I am skeptical about that last line. According to W|A it is giving me a horrendous-looking solution.
Never mind, forget W|A, it is unable to solve the problem so I do not trust its solution.
In mathematics, you don't understand things. You just get used to them.
Some cause happiness wherever they go; others, whenever they go.
If you can not overcome with talent...overcome with effort.
Where can you get with the substitution x=(b-a)-a*cos(theta)?
Last edited by anonimnystefy (2012-10-08 11:02:52)
The limit operator is just an excuse for doing something you know you can't.
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