X^2 - 3X = A ; A > 0
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A + 2 √ A = 0
2 √ A = - A
√ 4A = - A
4A = A^2
A^2 - 4A = 0
A * ( A - 4 ) = 0
A1 = 0
A2 = 4
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X^2 - 3X = 0
X * ( X - 3 ) = 0
X1 = 0
X2 = 3
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X^2 - 3X = 4
X^2 - 3X - 4 = 0
D = 9 + 16 = 25
√ D = 5
X1 = ( 3 + 5 ) : 2 = 4
X2 = ( 3 - 5 ) : 2 = - 1
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ОТВЕТ : 0 ; 3 ; 4 ; - 1