Question

Find the 300th term ofSn = 1/2 n - 25

Answer 1

The 300th term will be the difference of the sum of the first 300 terms and the sum of first 299 terms so it follows:

`\begin{gathered} S_(300)=(1)/(2)(300)-25=125 \\ S_(299)=(1)/(2)(299)-25=124.5 \end{gathered}`

Therefore the 300th term is given by:

`T_(300)=S_(300)-S_(299)=125-124.5=0.5`

Hence the 300th term is 0.5.