# Hint: don't use multinomial

Algebra Level 4

Let $$(2x^{2} + 3x +4)^{10} = \displaystyle \sum_{r = 0}^{20} a_{r}x^{r}$$, where $$a_0, a_1, \ldots , a_{20}$$ are constants.

Find the value of $$\dfrac{a_{7}}{a_{13}}$$.

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