If $f\left(x\right)=2x^6+3x^4+4x^2$ , then $f\text{'}\left(x\right)$ is

Since,
Now, $f\left(x\right)=2x^6+3x^4+4x^2$
$f\left(-x\right)=2{\left(-x\right)}^6+3{\left(-x\right)}^4+4{\left(-x\right)}^2$ 
$=2x^6+3x^4+4x^2=f\left(x\right)$ 
$\therefore f\left(x\right)$  is an even function and derivative of an even function is always an odd function.