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Arcus Tangent Calculator

With this arcus tangent calculator you'll quickly find the inverse of a tangent.

Clear
arcsin30°0.5235987756 radians
In radians0.5235987756
arcsin30°
arccos60°
arctan26.565051°
Check0.5the function applied back to the answer

The formula

arcsin, arccos and arctan undo the trig functions

Principal values

Each trig function repeats, so its inverse would have infinitely many answers. The convention is to return one principal value:

  • arcsin and arctan — from −90° to 90°
  • arccos — from 0° to 180°

So arcsin(0.5) gives 30°, even though 150° also has a sine of 0.5. When solving an equation you usually need both.