Question

For what value of k, is −2 a zero of the polynomial 3x² + 4x + 2k?

Answer 1

We know that if  `x = a` is zero polynomial then  `x-a` is a factor of  `f(x)`

Since - 2 is a factor of `f(x)`.Therefore `x+2` is a factor of  `f(x)`

Now, we divide`f(x) = 3x^2 + 4x + 2x ` by  `g(x)=x + 2` to find the value of k

Now, Remainder  = 0

`2k +4=0`

`2k = -4`

`k = (-4)/2`

`k = -2 `

Hence, the value of k is `-2 `