Question

найдите tg2A, если sin2A= -1/3

Answer 1

найдите tg2A, если sin2A= -1/3

tg2α = Sin2α/Cos2α

Cos²2α = 1 - Sin²2α = 1 -1/9 = 8/9

Сos2α = +-√8/9 = +-2√2/3

tg2α = -1/3 : ( +- 2√2/3) = +-1/(2√2) = +-√2/4

tg2α = +-√2/4