Question

УПРОСТИТЕ; tgl·tgB+(tgl+tgB)·ctg(l+B) PLZ MNOGOYE HELP

Answer 1

tgα·tgβ+(tgα+tgβ)·ctg(α+β) = $tg\alpha tg\beta +(tg\alpha +tg\beta) \frac{1-tg\alpha tg\beta}{tg\alpha+tg\beta} =tg\alpha tg\beta +1-tg\alpha tg\beta = 1$