Question

if α and β are the zeros of the quadratic polynomial ax²+bx+c,then the value of α+β is​

Answer 1

Answer:

-b/a is value of alpha+beta

Answer 2

ax2+bx+c=0  

α+β=−b/a,αβ=c/a  

From the first equation you get:  α2+2αβ+β2=b2a2  

Then you subtract  4αβ , which is 4c/a:  α2−2αβ+β2=b2a2−4ca=b2−4aca2  

Take square root of both sides(don’t forget the plus minus)  α−β=±b2−4ac−−−−−−−√a  

⋅⋅  

⌣