If $x = 2$ is a root of the polynomial $f(x) = 2x^2-3x + 7a$, find the value of $a$.
Given :
The given polynomial is $f(x) = 2x^2-3x + 7a$.
$x = 2$ is a root of the polynomial $f(x) = 2x^2-3x + 7a$.
To find :
We have to find the value of $a$.
Solution :
The zero of the polynomial is defined as any real value of $x$, for which the value of the polynomial becomes zero.
Therefore,
Zero of the polynomial $f(2)= 2(2)^2-3(2)+7a=0$
$2(4)-6+7a=0$
$7a=6-8$
$7a=-2$
$a=\frac{-2}{7}$
The value of $a$ is $\frac{-2}{7}$.
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