Предмет: Алгебра, автор: miku20147

помогите пожалуйста
полное решение ​

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Автор ответа: Pelmeshka83
1

Ответ:

 { \tan {}^{2} (x) } - 5 = 4 \tan(x)  \\  \tan(x)  = y \\  {y}^{2}  - 5 = 4y \\  {y}^{2}  - 4y - 5 = 0 \\ y1y2 =  - 5 \\ y1  + y2 = 4 \\  \\ y1 = 5 \\ y2 =  - 1 \\  \\  \tan1(x)  = 5 \\  \tan2(x)  =  - 1 \\  \\ x1 = arctan(5) \\  \\ x = arctan(5) + k\pi \:  \\  \\ x2 =  \frac{3\pi}{4}

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