5
10sin^2x - 3sin2x = 8
10sin^2x - 6sinxcosx = 8
10tg^2x - 6tgx = 8/cos^2x = 8(tg^2x + 1)
2tg^2x - 6tgx - 8 = 0
tg^2x - 3tgx - 4 = 0
(tgx + 1)(tgx - 4) = 0
tgx = -1 -> x = -П/4 + Пk
tgx = 4 -> x = arctg(4) + Пk
6
11sin2x - 6cos^2x + 8cos2x = 8
22sinxcosx - 6cos^2x + 8cos^2x - 8sin^2x = 8 |/cos^2x
22tgx + 2 - 8tg^2x = 8/cos^2x = 8(tg^2x + 1)
16tg^2x - 22tgx + 6 = 0
8tg^2x - 11tgx + 3 = 0
tgx = (11 +- sqrt(121 - 96))/16 = (11 +-5)/16
tgx = 1 -> x = П/4 + Пk
tgx = 3/8 -> x = arctg(3/8) + Пk