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How to Calculate Tan

What is Tan?

The tangent function (tan) is the ratio of the opposite side to the adjacent side, equivalent to sin(θ)/cos(θ). Tangent represents the slope of the line from the origin to a point on the unit circle.

Formula

tan(θ) = opposite / adjacent = sin(θ) / cos(θ)

Step-by-Step Guide

  1. 1tan(θ) = opposite / adjacent = sin(θ) / cos(θ)
  2. 2Undefined at 90° and 270° (where cos = 0)
  3. 3tan(45°) = 1 (slope of a 45° line)
  4. 4Period of tangent is 180° (π radians)

Worked Examples

Input
tan(45°)
Result
1
Equal opposite and adjacent sides
Input
tan(30°)
Result
0.5774
1/√3
Input
tan(89°)
Result
57.29
Approaches infinity at 90°

Frequently Asked Questions

What is Tan Calc?

The tangent function (tan) is the ratio of the opposite side to the adjacent side, equivalent to sin(θ)/cos(θ). Tangent represents the slope of the line from the origin to a point on the unit circle

How accurate is the Tan Calc calculator?

The calculator uses the standard published formula for tan calc. Results are accurate to the precision of the inputs you provide. For financial, medical, or legal decisions, always verify with a qualified professional.

What units does the Tan Calc calculator use?

This calculator works with inches. You can enter values in the units shown — the calculator handles all conversions internally.

What formula does the Tan Calc calculator use?

The core formula is: tan(θ) = opposite / adjacent = sin(θ) / cos(θ). Each step in the calculation is shown so you can verify the result manually.

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