Arcus Tangent Calculator

Arcus tangent is one of inverse functions in trigonometry: the inverse of tangent. In other words, it answers the question: what angle what used to produce this specific tangent value?. More formally, if the tangent of some angle α ∈ (-π/2, π/2) is equal to x, i.e.,

x = tan α

then arcus tangent allows you to recover α given x:

α = arctan(x).

Here's the graph of the arcus tangent function:

As you can see, it assumes values in the interval (-π/2, π/2). This is because tangent is many-to-one function, while only one-to-one functions have an inverse. Hence, before inverting, tangent must be restricted to an interval where it is one-to-one. This interval is usually taken to be (-π/2, π/2).

That's why we've stressed the angle α considered above is taken from the interval (-π/2, π/2).

Having discussed the range, let us say a few words about the domain of the arcus tangent function.

The domain of the arcus tangent is all real numbers. To see this, recall that the domain of an inverse function is the range of the original function. Since the range of the tangent is all real numbers, we easily get the answer.

To use this arcus tangent calculator, you just need to input the number for which you want to compute the arcus tangent. Since the domain of the arcus tangent is the whole set of real numbers, every input will do.

Tip: this arcus tangent calculator can work in reverse too! In other words, it can function as a regular tangent calculator. Just input the angle into the field y and enjoy the result!

features a mini-collection of tools related to inverting the tangent function:

• Arctan calculator;
• Tan-1 calculator;
• Tan inverse calculator; and
• Inverse tangent calculator.