The function is
and the point is
.
Apply derivative on each side with respect to
.

Derivative of inverse trigonometric function
.
Derivative of inverse trigonometric function
.



Derivative of the function is
.
Slope of the line is the first derivative of the function at the point
.
Substitute
in the derivative of the function.

Point-slope form of line equation is
.


The tangent line equation is
.