ACOT in WPS Spreadsheet: Recover an Angle from a Cotangent Ratio
Recover acute angles from positive cotangent ratios in WPS Spreadsheet, then convert the radian results to degrees.
Verification status: See the evidence and test scope described in this guide. How formula examples are checked
Quick answer: ACOT returns an inverse cotangent in radians. For the positive ratio one, =ACOT(1) has mathematical expected result 0.785398163 rad, or 45 degrees.
Availability and evidence scope
The official WPS Windows pages, checked October 19, 2026, document this function and advertise ordinary entry and calculation without membership. Their last-updated date is 2026-07-07; that is a documentation date, not its introduction release. They do not name an exact minimum or last supported build. Availability on Mac, Linux, mobile, web or historical builds is not established here.
The examples below are independently calculated mathematical expectations, rounded to nine decimal places where appropriate. They were not executed in WPS, and no native screenshot is claimed. Before relying on an installation, check its function prompt and run a small control example.
Syntax and arguments
=ACOT(number)
One required numeric argument, number, is the cotangent ratio. It is not a degree measurement. These examples deliberately use positive ratios; they do not establish the branch chosen by WPS for zero or negative inputs.
The documented Windows workflow supports typing the formula in a cell or choosing the function through Formula → Insert Function. These formulas use English names and comma separators. Inspect the destination formula after filling down so that relative references and fixed settings still point to the intended cells.
Example 1: recover three acute angles
A right-triangle worksheet stores adjacent/opposite ratios in A2:A4. Enter 1, 1.7320508075688772 and 0.5773502691896258. In B2 enter =ACOT(A2) and fill down. Expected radian values are 0.785398163, 0.523598776 and 1.047197551. In C2 use =B2*180/PI() and fill down: the expected degrees are 45, 30 and 60, allowing for the rounded ratios.
For this acute-angle example, a larger adjacent/opposite ratio corresponds to a smaller angle. Retain the radian column for later trigonometric calculations and label the converted column explicitly as degrees.
Example 2: reconstruct a triangle angle
Put adjacent length 12 in D2 and opposite length 5 in E2, using the same units. =ACOT(D2/E2) should give 0.394791120 radians. =ACOT(D2/E2)*180/PI() should give 22.619864948 degrees. The length units cancel in the ratio. This is a mathematical geometry example, not a method for selecting a signed bearing or quadrant from arbitrary coordinates.
Advanced check: an independent positive-input identity
For a positive number x, arccot(x)=atan(1/x). With A2=2.4, compare =ACOT(A2) with =ATAN(1/A2); both mathematical expectations are 0.394791120. This identity is a check for the selected positive inputs, not a replacement rule for every input. Negative inputs can expose different inverse-function branch conventions.
Check the round trip with =TAN(ACOT(A2))*A2: the expectation is approximately 1. A small residual is normal for rounded input and floating-point arithmetic; inspect several decimals rather than requiring textual equality.
Troubleshooting and limits
- A result near 0.7854 for input one is in radians. Converting it once gives 45 degrees; converting it twice is a unit error.
- Use adjacent/opposite for this example. Reversing the ratio changes the acute angle.
- The WPS FAQ advises checking numeric arguments when
#VALUE!appears. It does not define every coercion or error case. - The reviewed WPS prose does not establish the complete output interval, zero/negative branch choices, or extreme-input handling. The range in its Excel comparison is not a verified WPS contract.