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Math function
TAN
Returns the tangent of an angle in radians.
Rarely usedDifficulty 1100 · ProficientUsage rank #252 of 520
When to use it
Tangent of an angle in radians: rise over run. Slopes, gradients, and heights from angles.
The shape of it
- Syntax
=TAN(number)
Worked examples
45 degrees
=TAN(RADIANS(45)) → 1
A 45° slope rises one for every one across.
Flat
=TAN(0) → 0
Flat.
60 degrees
=TAN(RADIANS(60)) → 1.732050808
The square root of 3.
Worth knowing
- Height of a building: distance*TAN(angle of elevation).
- Grade percentage: TAN(angle)*100.
- ATAN inverts it; ATAN2 handles all four quadrants.
Where it goes wrong
- Near 90° the value explodes; TAN(PI()/2) returns 1.6E+16 rather than an error.
- Degrees must be converted first.
Related
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