If ddx[1+x2+x41+x+x2]=ax+b, then (a,b)=

$\frac{d}{d x} [\frac{1 + x^{2} + x^{4}}{1 + x + x^{2}}] = a x + b$

$\frac{d}{d x} [\frac{{(x^{2} + 1)}^{2} - x^{2}}{1 + x + x^{2}}] = a x + b$

$\frac{d}{d x} [\frac{(x^{2} + 1 + x) (x^{2} + 1 - x)}{(1 + x + x^{2})}] = a x + b$

$\Rightarrow 2 x - 1 = a x + b$

$a = 2, b = - 1$

$(a, b) = (2, - 1)$

If $\frac{d}{d x} [\frac{1 + x^{2} + x^{4}}{1 + x + x^{2}}] = a x + b$ , then $(a, b) =$