Question

If α and β are the zeros of the quadratic polynomial f(x)= x(x-4), find the value of 1/α +1/β -2αβ.​

Answer 1

I am assuming that you know the values of co efficents theorem since you have asked this.

f(x)=x(x-4)

    =x²-4x

In this, a=1;b=-4; and c=0

 α+β=-b/a              and   αβ=c/a      

     =-(-4)/1                            =0/1

     =4                                   =0

Now,

1/α+1/β-2αβ

=(α+β)/αβ-2αβ

=4/0-0

=∞        (any number x/0=∞)

This is the answer i can derive unless there is something wrong from the question