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:
Very common error! Exponents can only distribute to the ones in the brackets IF there is no addition or subtraction sign …. if there is then you need to just copy the bracket out again and the distribute.
Very common error! Exponents can only distribute to the ones in the brackets IF there is no addition or subtraction sign …. if there is then you need to just copy the bracket out again and the distribute.