a simple and hard trig equation proof
- Thread starter faditos
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Please show us what you have tried and exactly where you are stuck.
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Dr.Peterson
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I'll type out the problem, translating a bit:
Given that f(x) = 1 - 4 cos^2(x) + 2sin(x)cos(x), for -pi/2 < x < pi/2, express f(x) as a function of tan(x).
I would start by letting u = tan(x), so that we want to write f(x) in terms of u. That makes it easier to understand the goal.
Then I'd express sin(x) and cos(x) in terms of u, and then put it all together.
Please make some attempt and show it to us, so we can comment on it.