If an annuity makes an infinite series of equal payments at the end of the interest periods, it is called a perpetuity. If a lump sum investment of An is needed to result in n periodic payments of R when the interest rate per period is i, then the sum is represented by the following.
An = R 1 - (1 + i)^-n
i


Evaluate the following limit to find a formula for the lump sum payment for a perpetuity.

lim An
n?

Respuesta :

Answer:

[tex]lim_{n \to \infty} A_n = \frac{R}{i}[/tex]

Step-by-step explanation:

For this case we have this expression:

[tex] A_n = R [\frac{1 -(1+i)^{-n}}{i}][/tex]

The lump sum investment of An is needed to result in n periodic payments of R when the interest rate per period is i.

And we want to find the:

[tex] lim_{n \to \infty} A_n[/tex]

So we have this:

[tex] lim_{n \to \infty} A_n = lim_{n \to \infty}R [\frac{1 -(1+i)^{-n}}{i}] [/tex]

Then we can do this:

[tex] lim_{n \to \infty} A_n = lim_{n \to \infty} R [\frac{1 -\frac{1}{(1+i)^n}}{i}][/tex]

[tex]lim_{n \to \infty} A_n = R lim_{n \to \infty} [\frac{1 -\frac{1}{(1+i)^n}}{i}][/tex]

And after find the limit we got:

[tex] lim_{n \to \infty} A_n = R [\frac{1-0}{i}][/tex]

Becuase : [tex] \frac{1}{(1+i)^{\infty}} =0[/tex]

And then finally we have this:

[tex]lim_{n \to \infty} A_n = \frac{R}{i}[/tex]