(1)x平方-5x=-4 (2)2x平方-3x-1=0 (3)(X-1)(X+1)=X(4)X(2X+5)=2(2X+5) (5)(2X-1)平方=4(x+3)平方 (6)3(x-2)平方-9=0
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![(1)x平方-5x=-4 (2)2x平方-3x-1=0 (3)(X-1)(X+1)=X(4)X(2X+5)=2(2X+5) (5)(2X-1)平方=4(x+3)平方 (6)3(x-2)平方-9=0](/uploads/image/z/1691500-4-0.jpg?t=%EF%BC%881%EF%BC%89x%E5%B9%B3%E6%96%B9-5x%3D-4+%EF%BC%882%EF%BC%892x%E5%B9%B3%E6%96%B9-3x-1%3D0+%283%29%28X-1%29%28X%2B1%29%3DX%EF%BC%884%29X%282X%2B5%29%3D2%282X%2B5%29+%285%29%282X-1%29%E5%B9%B3%E6%96%B9%3D4%EF%BC%88x%2B3%EF%BC%89%E5%B9%B3%E6%96%B9+%EF%BC%886%EF%BC%893%EF%BC%88x-2%EF%BC%89%E5%B9%B3%E6%96%B9-9%3D0)
(1)x平方-5x=-4 (2)2x平方-3x-1=0 (3)(X-1)(X+1)=X(4)X(2X+5)=2(2X+5) (5)(2X-1)平方=4(x+3)平方 (6)3(x-2)平方-9=0
(1)x平方-5x=-4 (2)2x平方-3x-1=0 (3)(X-1)(X+1)=X
(4)X(2X+5)=2(2X+5) (5)(2X-1)平方=4(x+3)平方 (6)3(x-2)平方-9=0
(1)x平方-5x=-4 (2)2x平方-3x-1=0 (3)(X-1)(X+1)=X(4)X(2X+5)=2(2X+5) (5)(2X-1)平方=4(x+3)平方 (6)3(x-2)平方-9=0
(1)
x²-5x=-4
x²-5x+4=0
(x-1)(x-4)=0
x=1或x=4
(2)
2x²-3x-1=0
Δ=(-3)²-4*2*(-1)=17
x=(3±√17)/4
(3)
(x-1)(x+1)=x
x²-1=x
x²-x-1=0
Δ=(-1)²-4*1*(-1)=5
x=(1±√5)/2
(4)
x(2x+5)=2(2x+5)
(x-2)(2x+5)=0
x=2或x=-5/2
(5)
(2x-1)²=4(x+3)²
(2x-1)²-4(x+3)²=0
[(2x-1)-2(x+3)][(2x-1)+2(x+3)]=0
-7(4x+5)=0
x=-5/4
(6)
3(x-2)²-9=0
(x-2)²-3=0
(x-2)²=3
x-2=±√3
x=2±√3
1)
x²-5x=-4
x²-5x+4=0
(x-1)(x-4)=0
x=1或x=4
(2)
2x²-3x-1=0
Δ=(-3)²-4*2*(-1)=17
x=(3±√17)/4
(3)
(x-1)(x+1)=x
x²-1=x
x²-x-1=0...
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1)
x²-5x=-4
x²-5x+4=0
(x-1)(x-4)=0
x=1或x=4
(2)
2x²-3x-1=0
Δ=(-3)²-4*2*(-1)=17
x=(3±√17)/4
(3)
(x-1)(x+1)=x
x²-1=x
x²-x-1=0
Δ=(-1)²-4*1*(-1)=5
x=(1±√5)/2
(4)
x(2x+5)=2(2x+5)
(x-2)(2x+5)=0
x=2或x=-5/2
(5)
(2x-1)²=4(x+3)²
(2x-1)²-4(x+3)²=0
[(2x-1)-2(x+3)][(2x-1)+2(x+3)]=0
-7(4x+5)=0
x=-5/4
(6)
3(x-2)²-9=0
(x-2)²-3=0
(x-2)²=3
x-2=±√3
x=2±√3
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