Question

Determine the 4th term in the geometric sequence whose first term is -2 and whose common ratio is -5

Answer 1

`\bf n^(th)\textit{ term of a geometric sequence}\\\\ a_n=a_1\cdot r^(n-1)\qquad \begin{cases} a_1=\textit{first term}\\ r=\textit{common ratio}\\ n=n^(th)\ term\\ -------\\ a_1=-2\\ r=-5\\ n=4 \end{cases}\implies a_4=(-2)(-5)^(4-1)`