X^4 - 5X^2 + 4 = 0
X^2 = A ; A > 0
A^2 - 5A + 4 = 0
D = 25 - 16 = 9 ; √ D = 3
A1 = ( 5 + 3 ) : 2 = 4
A2 = 2 : 2 = 1
X1 = + 2
X2 = - 2
X3 = + 1
X4 = - 1
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9X^2 - 37X = 0
9X * ( X - 37 ) = 0
9X = 0 ; X = 0
X - 37 = 0 ; X = 37
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2 1/5 X + 4,2 = 1 1/3 * ( 2 - X )
2,2X + 4,2 = 4/3 * 2 - 4/3X
2,2X + 4,2 = 8/3 - 4/3X
2,2X + 4/3X = 8/3 - 4,2
22/10X + 4/3X = 8/3 - 21/5
22X * 3 + 4X * 10 = 8 * 10 - 21 * 6
66X + 40X = 80 - 126
106X = - 46
X = - 46/106 = - 23/53
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( 1/ X^2 ) + ( 1/ X) + ( 6/ X ) = ( - 4 * ( 1+ X^2 ) / X^2 )
X^2 ≠ 0 ; X ≠ 0
( 1 + X + 6X ) / X^2 = ( - 4 - 4X^2 ) / X^2
1 + 7X = - 4 - 4X^2
4X^2 + 7X + 5 = 0
D = 49 - 80 = - 31
D < 0
Решений нет