Question

设a.b是方程x*2-x-3=0的两根,则（a*-1+b*-1)/(ab)*-1的值为多少?

Answer 1

设a.b是方程x*2-x-3=0的两根,

a+b=1;

ab=-3;

则（a*-1+b*-1)/(ab)*-1的值为多少?

=(1/a+1/b)/(1/ab)

=b+a

=1;