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i. Show that $d^{(p)}$, the nominal rate of discount payable $p$ times a year, can be written as $d^{(p)}=p\left(1-e^{-\delta / p}\right)$, where $\delta$ is the force of interest.

ii. Starting from the equation derived in i., show that $\lim _{p \rightarrow \infty} d^{(p)}=\delta$.
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(i)
\begin{aligned} &\left(1-\frac{d^{(p)}}{p}\right)^{p}=v=e^{-\delta} \Rightarrow\left(1-\frac{d^{(p)}}{p}\right)=e^{-\delta / p} \\ &\frac{d^{(p)}}{p}=1-e^{-\delta / p} \Rightarrow d^{(p)}=p\left(1-e^{-\delta i p}\right) \end{aligned}
(ii)
\begin{aligned} &\lim _{p \rightarrow \infty} d^{(p)}=\lim _{p \rightarrow \infty}\left[p\left(1-e^{-\delta / p}\right)\right]=\lim _{p \rightarrow \infty}\left[p\left(1-\left(1-\frac{\delta}{p}+\frac{\delta^{2}}{2 ! p^{2}}-\ldots\right)\right)\right] \\ &=\lim _{p \rightarrow \infty}\left[p\left(\frac{\delta}{p}+\frac{\delta^{2}}{2 ! p^{2}}-\ldots\right)\right]=\lim _{p \rightarrow \infty}\left[\delta-\frac{\delta^{2}}{2 ! p}+\frac{\delta^{3}}{3 ! p^{2}} \ldots\right]=\delta \end{aligned}
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