Trang chủ » Hỏi đáp » Môn Toán 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 19/12/2024 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)
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) Trả lời
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”