Question

Sabendo que tg x= 3, calcule tg (x - π\4)

Answer 1

$tan(\alpha-\beta)= \frac{tan(\alpha)-tan(\beta)}{1+tan(\alpha).tan(\beta)} \\ tan(x-\pi/4)= \frac{tan(x)-tan(\pi/4)}{1+tan(x).tan(\pi/4)} = \frac{3-1}{1+3.1} = \frac{2}{4} = \frac{1}{2}$