how do i do this problem?

 Write a function M-file called par_res that 
– takes as input two resistor values (say R1 and R2), and 
– outputs the equivalent resistance, say R_eq, if the two resistors are in parallel.

[MEHABOOBSUBANI GULEDKOPP]

function R_eq = par_res(R1,R2)

R_eq = R1*R2/(R1+R2);

end

[Kamran Salehi]

do you know how I can do that with a test script and function script?