How do you enter an array formula in Excel?

In Excel, entering an array formula requires a specific method to ensure that the formula processes multiple values or calculations simultaneously. When you want to enter an array formula, you need to use the keyboard shortcut Ctrl + Shift + Enter after typing the formula. This action tells Excel that the formula should be treated as an array formula, which can evaluate ranges of cells and return multiple results or perform multiple operations in a single formula.

When you correctly enter an array formula, Excel will automatically enclose the formula with curly braces (for example, {=SUM(A1:A10*B1:B10)}), indicating that it has acknowledged the formula as an array formula. This key distinction allows for functions and operations that operate across ranges of data rather than a single cell input.

Other methods, such as simply pressing Enter or clicking on 'Insert', only process standard formulas and do not invoke the array capabilities that are essential for performing complex calculations involving multiple data points. Similarly, enclosing a formula within brackets is not a recognized method for entering array formulas in Excel. Understanding this ensures that you're able to leverage the full power of Excel's formula capabilities effectively.