Quickly Calculate the Square of a Number

The square of a number, written with ², is a mathematical function whose result is the number multiplied by itself. For example, if A is a number, its square, written A², is equal to A * A. In short: A² = A * A.

Negative and positive numbers

Since the number is multiplied by itself, and a math rule reminds us that a negative number multiplied by another negative number produces a positive number (- * - = +), it is interesting to note that the square of a negative number is always equal to the square of the corresponding positive number.

In short: A² = (-A)² = A * A = -A * -A. Let's take a concrete example with the number 9 => 9² = (-9)² = 81.

What is the link between the square of a number and its square root?

The square root is, in a way, the opposite operation. Starting from a number A, it finds the number B which gives A when B is multiplied by itself. Put simply, A² = √A² * √A². Or even simpler: 9² = 81 and √81 = 9. You can quickly calculate the square root with this calculator.

Shortcuts

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f ⇝ Save

Squares of whole numbers (non-exhaustive list)

Squares of the numbers 1 to 15.

• 1² = 1
• 2² = 4
• 3² = 9
• 4² = 16
• 5² = 25
• 6² = 36
• 7² = 49
• 8² = 64
• 9² = 81
• 10² = 100
• 11² = 121
• 12² = 144
• 13² = 169
• 14² = 196
• 15² = 225

Save

Saving lets you keep the calculations you make. You can save a number and its square, then export them in PDF or CSV format.