use the trigonometric ratios for a right triangle to derive a cofunction identity for tan(90degrees-A)

Question

jack1 · Answer

so do you know SOH CAH TOA?

in this case TOA ==>  Tan (theta) = Opposite/ Adjacent

so theta = 90 - A
which means its a right angle triangle with 90 degrees for one angle, A degrees for the other angle, and (90-A) degrees for the 3rd angle

jack1 · Answer

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does this make sense???

anonymous · Answer

that makes sense but how do I derive the cofunction identity using the trig ration$$tantheta=1/\cot$$

mathmate · Answer

Another hint:
$$tan \theta=opp/adj$$
$$cot \theta=adj/opp$$
and study Jack's diagram again.

anonymous · Answer

I'm just having trouble applying this, how can I figure any side out from just one angle?