We can use the binomial theorem, which states that for any positive integer $n$ and any real numbers $a$ and $b$:
$(a+b)^n = \sum_{k=0}^{n} \binom{n}{k} a^{n-k} b^k$
In our case, $n=6$, $a=2$, and $b=px$. So, we have:
$(2+px)^6 = \sum_{k=0}^{6} \binom{6}{k}
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