1. (3x(x-3)+3(x+3)-2x*x)/x(x+3)(x-3) = (3x*x-9x+3x+9-2x*x)/x(x+3)(x-3) = (x*x-6x+9)/x(x+3)(x-3) = ((x-3)(x-3))/x(x-3)(x+3) = 1/x(x+3)
Ctgx=корень из 3 на 3
х=2пи/3+пиN
- X - Y - Z = - 4
X + Y - Z = 2
- 2Z = - 2
Z = 1
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X + Y = 4 - 1
X + Y = 3
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2X - Y = 1 - 1
2X - Y = 0
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X + Y = 3
Y = 3 - X
2X - ( 3 - X) = 0
2X - 3 + X = 0
3X = 3
X = 1
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1 + Y = 3
Y = 3 - 1
Y = 2
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Ответ X = 1; Y = 2 ; Z = 1
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Проверка
1) 1 + 2 + 1 = 4 ; 4 = 4
2) 1 + 2 - 1 = 2 ; 2 = 2
3) 2 - 2 + 1 = 1 ; 1 = 1