Final answer:
To simplify the expression 3a²b + 4a²b - a²b, you combine the coefficients of the like terms to get 6a²b.
Step-by-step explanation:
The student has asked to simplify the expression 3a²b + 4a²b - a²b. To simplify this, you combine like terms, which in this case are all the terms because they all contain a²b.
You would add or subtract the coefficients (the numbers in front of the variable terms) which are 3, 4, and -1 (assuming 'a' represents -1 for the last term). So the calculation would be:
3 + 4 - 1 = 6
Therefore, the simplified version of the expression is 6a²b, since we combined the coefficients and kept the variable part of the terms the same.