Crimson_p

(x+1)(2x-3)=4x^2-9

(x+1)(2x-3) = (2x-3)(2x+3)
(x+1)(2x-3) - (2x-3)(2x+3) = 0
[(x+1)-(2x+3) ] (2x-3) = 0
(-x-2)(2x-3) = 0

x= -2 , x= 3/2

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(2x+3)(3x-1)=35
6x²+7x-3 = 35
6x²+7x-38 = 0
(6x+19)(x-2) = 0

x= -19/6 , x= 2

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x(2x+3)=x(3x-4)
2x²+3x = 3x²-4x
x²-7x = 0
x(x-7) = 0

x = 0,  x=7

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(1-x)(x+4) = (x+1)²
-x²-3x+4 = x²+2x+1
-2x²-5+3 = 0
(-2x+1)(x+3)=0

x = 1/2 , x= -3




未必岩晒

[ 本帖最後由 Crimson_p 於 2008-10-11 16:55 編輯 ]

Crimson_p

仲有冇人問f4 math