Предмет: Алгебра, автор: threkhdkKatevakala

sin ^2x-2sin x cos x= 3 cos ^2x

Ответы

Автор ответа: Аноним

Это однородное уравнение
Sin²x -2Sinx Cosx -3Cos²x = 0 | :Cos²x
tg²x - 2tg x -3 = 0
Решаем как квадратное
По т. Виета
а) tgх = 3 б) tgx = -1
х = arctg3 + πk, k∈Z x = -π/4 + πn, n∈Z

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