(sinx - cosx) - 1 + 4* sin2x = ?
Sin²x + cos²x - 2sinxcosx - 1 + 4sin2x = 1 - sin2x - 1 + 4sin2x = 3sin2x Ответ: 3sin2x
(sin²x+cos²x-2sinxcosx) -1+4sin2x = 1-2sinxcosx-1 +4sin2x = -sin2x+4sin2x= 3sin2x