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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.
No explanations, just DGA.
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.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment