Classmate, is your formula one the n power of V? Maybe you forgot to write it. In principle, it should be converted from n cycles to 0 moments.

Meaning of formula 1:

The present value of permanent final annuity is equal to the present value of N-year final annuity plus the present value of N-year final annuity converted to zero.

Equation 2:

The sum of accumulated principal and interest in N years under compound interest I is equal to the sum of 0 time 1 unit principal plus interest rate I and the final value of N years.

I hope it helps you. If you don't understand, you can continue to ask.