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解方程%2x^3+3x^2%1=0怎么解

-2x^3+3x^2-1=0 2x^3-3x^2+1=0 2x^2(x-1)-(x^2-1)=0 2x^2(x-1)-(x+1)(x-1)=0 (x-1)(2x^2-x-1)=0 (x-1)(x-1)(2x+1)=0 (x-1)^2(2x+1)=0 (x-1)^2=0,x=1 2x+1=0,x=-1/2

2x³-x²-1=(x³-1)+(x³-x²)=(x-1)(x²+x+1)+x²(x-1)=(x-1)(2x²+x+1)=0 2x²+x+1=2(x+1/4)²+7/8>0恒成立 ∴x-1=0 ∴x=1

x^4+2x^3+x^2-1=0 x^4+2x^3+x^2=1 x^2 (x^2+2x+1)=1 x^2*(x+1)^2=1 (x(x+1))^2=1 x(x+1)=1或=-1 x^+x-1=0或x^+x+1=0 前面的 x1=(-1-√5)/2 ,x2=(-1+√5)/2 后面的无解

(3x+1)^2=9(2x+3)^2 (3x+1)²=[3(2x+3)]² 3x+1=±3(2x+3)=±(6x+9) ∴3x+1=6x+9→3x=-8→x=-8/3 3x+1=-6x-9→9x=-10→x=-10/9

syms xsolve(2*x^3+3*x-2)这样求解得不到根,就可以直接roots([2,0,3,-2])ans = -0.2768 + 1.3152i -0.2768 - 1.3152i 0.5536 + 0.0000i

你化错了. 应该是 1 0 0 1 0 1 0 2 0 0 1 1 0 0 0 0

x1是x下角一个1吗?

1:x^3-3x^2+2x-300000=0 x^3-3x^2+3x-1-x+1-30000=0 (x-1)^3-(x-1)-300000=0 x(x-1)(x-2)=300000

由2x3-3x2+1=0,得2x3-2x2-x2+1=0,即2x2(x-1)-(x2-1)=0,因式分解得:(x-1)2(2x+1)=0.解得:x=1或x=-12.

解 (x-2)²=(2x+3)² x²-4x+4=4x²+12x+9 即 3x²+16x+5=0 (3x+1)(x+5)=0 ∴x=-5 或x=-1/3

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