MATLAB

Electrical resistors are said to be connected in series if the same current passes through each and in parallel if the same voltage is applied across each.

If in series they are equivalent to a single resistance given by: R_equivalent = R1 + R2 +R3 +......+ Rn

If in parallel, their equivalent resistance is given by: 1/R_equivalent = 1/R1 + 1/R2 + 1/R3 +......+ 1/Rn

where Rn is the nth resistor. Write a function that takes two inputs (a vector of all of the resistances and a variable that describes whether they are in series or parallel). This function should output the equivalent resistance. Test your program by calculating the equivalent resistance for a parallel circuit with three resistors: R1 = 4ohms, R2 = 5 ohms, and R3 = 9 ohms.