Tìm x a) (2x-1)²+x(5-4x)=0 b) 4x(x-3)-3+x=0 c)x³-6x²+9x=0 d)x²-9+(x-3)²=0 e)(x+3)(x-2)-(2x-5

Tìm x

a) (2x-1)²+x(5-4x)=0

b) 4x(x-3)-3+x=0

c)x³-6x²+9x=0

d)x²-9+(x-3)²=0

e)(x+3)(x-2)-(2x-5)(x+3)

1 bình luận về “Tìm x a) (2x-1)²+x(5-4x)=0 b) 4x(x-3)-3+x=0 c)x³-6x²+9x=0 d)x²-9+(x-3)²=0 e)(x+3)(x-2)-(2x-5”

  1. a) (2x-1)^2+x(5-4x)=0
    => 4x^2-4x+1+5x-4x^2=0
    => x+1=0
    => x=-1
    Vậy x=-1
    b) 4x(x-3)-3+x=0
    => 4x(x-3)+(x-3)=0
    => (4x+1)(x-3)=0
    TH1:
    4x+1=0
    => 4x=-1
    => x=-1/4
    TH2:
    x-3=0
    => x=3
    Vậy x∈{-1/4; 3}
    c) x^3-6x^2+9x=0
    => x(x^2-6x+9)=0
    => x(x-3)^2=0
    TH1:
    x=0
    TH2:
    (x-3)^2=0
    => x-3=0
    => x=3
    Vậy x∈{0; 3}
    d) x^2-9+(x-3)^2=0
    => (x-3)(x+3)+(x-3)^2=0
    => (x+3+x-3)(x-3)=0
    => 2x(x-3)=0
    TH1:
    2x=0
    => x=0
    TH2:
    x-3=0
    => x=3
    Vậy x∈{0; 3}
    d) (x+3)(x-2)-(2x-5)(x+3)
    =(x+3)(x-2-2x+5)
    =(x+3)(-x+3)
    =(x+3)(3-x) 

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