User:ShaunMacPherson/latex

${\begin{aligned}f'(3)&=\lim _{h\to 0}{(3+h)^{2}-9 \over {h}}\\&=\lim _{h\to 0}{9+6h+h^{2}-9 \over {h}}\\&=\lim _{h\to 0}{6h+h^{2} \over {h}}\\&=\lim _{h\to 0}(6+h)\\&=6.\end{aligned}}$

${\begin{aligned}Po=[(1-(1+k)^{(}-n))/k]+f(1+k)^{(}-n)\end{aligned}}$