Rewrite the above expression as an exponential summation expression:
Rewrite the above expression as an exponential summation expression:
To solve this problem, we will apply the square of a binomial formula.
The given expression is . We recognize this as the square of a binomial, which can be rewritten as . To expand this expression, we use the formula:
In our expression, and . Let's apply the formula:
Putting it all together, we have:
Therefore, the exponential summation expression is , with the expanded form:
This matches choice 3, confirming our solution.