1 .
The function $f : \mathbb{N} \rightarrow \mathbb{N}$ is defined by
$$
\begin{align}
f(0) &= 7 \\
f(n) &= f(n - 1) + 10n - 6\; \ \mathrm{for}\ n \geq 1
\end{align}
$$
What is $f(n)$?
(a)
$f(n) = 5n^2 - 2n + 7$
(b)
$f(n) = 4n^2 - n + 7$
(c)
$f(n) = 4n^2 - 2n + 7$
(d)
$f(n) = 5n^2 - n + 7$