SQRT in WPS Spreadsheet: Calculate Principal Square Roots with Clear Domain Checks

• Introduced: documented by 2019-05-17 in the official WPS lesson; original introduction is not established.
• Availability: WPS Office for Windows Personal; no numeric release is stated. This is documentation evidence, not an installed-build guarantee.
• Scope: the exact supported build range is unverified. The Windows lesson does not establish equivalent availability in other WPS clients.
• Checked: October 14, 2026 against function-specific documentation. Examples were independently calculated; no new native WPS test was performed.

=SQRT(number)

The WPS lesson’s formal note specifies #NUM! for a negative argument. Its informal walkthrough says the value must be positive, which omits the mathematical zero endpoint. This guide treats SQRT(0)=0 as the independently derived boundary control, rather than presenting that wording as a native test of zero.

Examples use English function names and decimal-point numbers. The dated Windows lesson supplies the function definition and negative-input rule; current build and broader client behavior remain unverified.

Enter 0, 1, 9, 25, 81 in A2:A6. In B2 enter =SQRT(A2) and fill down. Expected mathematical results are 0, 1, 3, 5, 9.

For a non-perfect square, =SQRT(2) has expected value approximately 1.414213562. Keep the unrounded formula result for later calculations instead of retyping the displayed digits.

A value of −1 falls outside the real domain and is assigned #NUM! by the cited lesson. That is a vendor-documented error expectation, not a captured result from a newly run WPS workbook.

For a constructed square with area 72 square units:

=SQRT(72)

Expected side length: approximately 8.485281374 units. Squaring the unrounded result reconstructs area 72. Units change from area units to length units because the operation is a square root.

This model assumes the figure is a square. The same area does not determine a unique side length for every rectangle; the formula cannot supply an unstated geometry assumption.

For perpendicular components of 5 and 12 units:

=SQRT(5^2+12^2)

Expected length: 13 units, because the squared components are 25 and 144, totaling 169. This is the Euclidean length under the stated perpendicular-coordinate model.

The two components need compatible units. Summing a squared distance and an unrelated squared count has no justified geometric meaning merely because the formula returns a number.

=SQRT((-7)^2)
=SQRT(7^2)

Expected results: 7 and 7. Squaring makes both source values 49, and SQRT returns the nonnegative branch. It cannot recover whether the original source was negative.

The corresponding mathematical identity is SQRT(x²)=ABS(x), not x for every real x. ABS is more direct when the requirement is magnitude and there is no reason to create a potentially large squared intermediate.

For the three controlled values 3, 4 and 0:

=SQRT((3^2+4^2+0^2)/3)

Expected result: approximately 2.886751346. The squared values total 25, their mean is 25/3, and the final square root restores the source unit.

The ordinary arithmetic mean is instead 7/3, approximately 2.333333333. These metrics answer different questions. Keep the definition and the count of three explicit rather than labeling both results average without qualification.

Check the sign of the stored argument, not only the rounded display. A computed value that is slightly negative can indicate a real invalid input or numerical cancellation; silently forcing it to zero can hide the cause.

The source does not provide every text-coercion or extreme-precision detail. These finite examples and mathematical identities do not certify native behavior across all WPS releases or support complex-valued roots through SQRT.

• WPS Academy: SQRT lesson, 2019-05-17 (Chinese; Windows Personal scope).
• Editorial testing standards.

The cited product lesson was read directly. Worked outputs are independent expectations, not captured native WPS results or proof of support across all current clients.