This week, I got half of the question correct, since my final answer was . However, the actual answer was and I could not figure out why. While I was going over the homework with my friends and discussing this one question, the solution suddenly popped into my head and the question finally made sense!

I had been adding and multiplying the exponents together, but that was only half the battle:

But the exponent meant that the binomial is multiplying by itself, so using distribution to solve the problem is the correct way to do it:

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