Question

Verify whether the indicated numbers are zeros of the polynomials corresponding to them in the following cases:

(vii) $f\left(x\right)=lx+m,x=-\frac{m}{l}$

Answer 1

Given : $f\left(x\right)=lx+m,x=-\frac{m}{l}$

We know that if $f\left(a\right)=0;$ then $a$ is the zero of the polynomial $f\left(x\right)$.

$\therefore f(-\frac{m}{l})=1\times -\frac{m}{l}+m$

$=-m+m=0$

$\because f(-\frac{m}{l})=0$

Hence, $x=-\frac{m}{l},$ is the zero of $f\left(x\right)=lx+m,$ verified.