utf06-001

Recall that $\sin^2 x = 1- \cos^2 x$. Write an expression for each trig function squared in terms of one of the other trig functions. $$a)   \cos^2 x              b)   \tan^2 x              c)   \cot^2 x              d)   \sec^2 x              e)   \csc^2 x$$

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Tags: trig-identities, trig, computation, a--a, t1, c1

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I think this is a pretty standard, but important exercise to work on, to remind them that they can rederive trig identities in a pinch. I personally like to push the “go back to the circle” approach, but don’t try to unteach any odd mnemonics they have.

– Eric Hsu 1998-08-09