Maths Question:
$\text{Find the formula }{{u}_{n}}\text{ for the sequence }1,-4,9,-16,25,\cdot \cdot \cdot $
Maths Solution:
$\begin{align} & {{U}_{1}}=1 \\ & {{U}_{2}}={{(-1)}^{2+1}}({{2}^{2}}) \\ & {{U}_{3}}={{(-1)}^{3+1}}({{3}^{2}}) \\ & {{U}_{4}}={{(-1)}^{4+1}}({{4}^{2}}) \\ & {{U}_{5}}={{(-1)}^{5+1}}({{5}^{2}}) \\ & {{U}_{n}}={{(-1)}^{n+1}}({{n}^{2}}) \\\end{align}$
University mathstopic: