Question

Find the zeroes of the quadratic polynomial `(5y^2 + 10y)` and verify the relation between the zeroes and the coefficients. 

Answer 1

We have, 

`f(u)=5u^2+10u` 

It can be written as 5u (u+2) 

∴ `f(u)=0⇒ 5u=0or u+2=0` 

              ⇒ `u=0 or u=-2 ` 

So, the zeroes of f (u) are −2 and 0.  

Sum of the zeroes =`-2+0=-2=(-2xx5)/(1xx5)=-10/5 -(("Coefficient of x"))/(("Coefficient of" u^2))` 

Product of zeroes=`-2xx0=0=(0xx5)/(1xx5)=-0/5= ("Constant term")/(("Coefficient of" u^2))`