求下列方程两根的和与积:
问题描述:
求下列方程两根的和与积:
x^2-3x+2=10
5x^2+x-5=0
x^2+x=5x+6
7x^2-5=x+8
x^2-5x-10=0
2x^2+7x+1=0
3x^2-1=2x+5
x(x-1)=3x+7
答
采用伟达定理即可x^2-3x+2=10x1+x2=3,x1x2=25x^2+x-5=0x1+x2=-1/5,x1x2=-1x^2+x=5x+6x1+x2=4,x1x2=-67x^2-5=x+8x1+x2=1/7,x1x2=-13/7x^2-5x-10=0x1+x2=5,x1x2=-102x^2+7x+1=0x1+x2=-7/2,x1x2=1/23x^2-1=2x+5x1+x2=2/...