解方程：x^3+9x^2=100,x^3+6=7x^2,x^3+3x^2=2 .每个方程仅有一解

解方程：x^3+9x^2=100,x^3+6=7x^2,x^3+3x^2=2 .每个方程仅有一解
解方程：x^3+9x^2=100,x^3+6=7x^2,x^3+3x^2=2 .
每个方程仅有一解

解方程：x^3+9x^2=100,x^3+6=7x^2,x^3+3x^2=2 .每个方程仅有一解
x^3+9x^2=100
x=-5,x=2(-1-6^0.5),x=2(-1+6^0.5)
x^3+6=7x^2
x=1,x=3-15^0.5,x=3+15^0.5
x^3+3x^2=2
x=-1,x=-1-3^0.5,x =-1+3^0.5