i need to make a program that asks for the amount of a loan, the interest rate, and the length of the loan using scanf. then i need it to tell me what the monthly payment is.

i want to use "a" as the amount of the loan, the monthly interest rate is r and n is the length of the loan in months. P is the monthly payment.

my equation should be this p=a(r((1+r)^n))/((1+r)^n)-1))

I really don't know what i'm doing... if someone could show me how to do the exponents is the main part. thanks.