Question

If A+B=90º and tan A=3/4, what is cot B?

Answer 1

$\tan(A + B) = \tan(90) \\ \frac{ \tan A + \tan B}{1 -\tan A \tan B } = \infty \\ therefore \\ 1 - \tan A \tan B = 0 \\ \tan B = \frac{1}{ \tan A} \\ \cot B = \tan A = \frac{3}{4}$