3 sin (2 [tex] \alpha [/tex] - [tex] \frac{ \pi }{4} [/tex]) + 2 cos (3 [tex] \alpha [/tex] - [tex] \pi [/tex])

если [tex] \alpha [/tex] = [tex] \frac{ \pi }{4} [/tex]

... = 3*sin((2*π/4) - (π/4)) + 2*cos((3*π/4) - π) == 3*sin(π/4) + 2*cos(-π/4) = 3*√2 / 2 + 2*√2 / 2 = 5√2 / 2косинус --- функция четная, т.е. cos(-x) = cos(x)