How would you simplify 2(x - 1) + x?
Do the same thing here.
I think I know where you made the mistake...
Ok, trick question: What is ? If you answered , you made a mistake.
Remember the rules on multiplying things with exponents with the same base?
is the same as , of course. And since you're multiplying, you need to add the exponents. So .
So, in fact, . Which makes your answer and definitely not .
Hope that clears it up! Easy mistake to make.