Final answer:
The expression that represents '8 less than twice the square of a number, n' is 2n^2 - 8.
Step-by-step explanation:
To represent "8 less than twice the square of a number, n," we start by identifying the operation that must be performed first. Since we need to square the number, we use n squared, which is n2. Next, we must apply twice to this result, leading to 2n2. Finally, we make the expression 8 less than this result, giving us 2n2 - 8.