Дано sinx=10/11. Найти cos2x-? sin2x-? tgx-?

Sin (x) = 10/11

cos (x) = sqrt (1-sin^2 (x)) = sqrt (1-100/121) = sqrt (21/121) = sqrt (21) / 11

sin (2x) = 2sin (x) cos (x) = 2 * (10/11) * (sqrt (21) / 11) = 20sqrt (21) / 121

cos (2x) = 1-2sin^2 (x) = 1-200/121=-79/121

tg (x) = sin (x) / cos (x) = (10/11) * (11/sqrt (21)) = 10/sqrt (21)

sqrt - корень