Questions that look like homework problems that may have been copied without the poster understanding the question, in which the poster shows no effort to answer it, are routinely closed, and I agree with the practice of closing those. Recently a question said this:
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How can I get
$$\sum_{k=0}^n\binom{n}{k}(pe^t)^kq^{n-k}=(pe^t+q)^n \text{ ?}$$
How can I get
∑k=0n(nk)(pet)kqn−k=(pet+q)n ?
I'm having a real problem, trying to figure out this equation. Can you, help me with that ?
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