14. The equation of a circle with its center is at and is given by

, where R is the radius of the circle. Write a program in a script file that first derives the equation

(symbolically) of the tangent line to the circle at the point on the upper part of the circle [i.e., for and

]. Then for specific values of R, , and the program makes a plot, like the one shown on the right, of the circle and the tangent line. Execute the program with and .