What is the difference between arctan and inverse tan?

The arc tangent of x is defined as the inverse tangent function of x when x is real. When the tangent of y is equal to x. Then the arc tangent of x is equal to the inverse tangent function of x, which is equal to y. I hope you are satisfied with my answer and feel free to ask for more if you have question and further clarifications

Hello,

It is not the same function.

arctan (tan (x)) = x

1/tan (x) * tan (x) = 1

in the file jointed,

arctan x is in blue

1/tan x in red.