Задача 54538 2sin(3Pi+x/2)cos(4Pi-x/2), x = 30...

5f89cb402123e0613fbe0e07

16.10.2020 21:11:38

2sin(3Pi+x/2)cos(4Pi-x/2), x = 30

5f3ea7e3faf909182968ddd9

16.10.2020 21:58:20

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[m]sin(\frac{3\pi}{2}+\frac{x}{2})=-sin\frac{x}{2}[/m]

[m] cos(4 \pi - \frac{x}{2})=cos(- \frac{x}{2})=cos\frac{x}{2})

[m]-2sin\frac{x}{2}\cdot cos \frac{x}{2}=-sinx[/m]

При x=30 °

[m] -sin30^{o}=-\frac{1}{2}=-0,5[/m]

Ответ: -0,5