Extended Euclidean algorithm and extended remainder sequence

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Consider the rational polynomials $h,f$:

$h:=x^8+x^6-3x^4-3x^3+8x^2+3x-5$

$f:=3x^6+5x^4-4x^2-9x+2$

Compute polynomials $r,t \in \mathbb{Q}[x]$ such that

$r\equiv tf \mod{h}$ with $\deg r < 4, \deg t \leq 4$.

The hint is to write down the extended remainder sequence produced when executed the extended Euclidean algorithm on the input $(h,f)$ and to decide which of the triplets $(r_i,s_i,t_i)$ determine rational function approximations, i.e., a pair $(r,t)$ of polynomials in $\mathbb{Q}[x]$ such that $\deg r < n, \deg t \leq n - \deg r$ and so that

$\gcd(t,h)=1$ and $rt^{-1} \equiv f \mod{h}$

I an compute the extended Euclidean algorithm using computer algebra however I'm not sure what's meant by the "extended remainder sequence" or how to continue with this result.