Write down the 20^{th} term of the G.P. 1, -1 | vedclass

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(B) The given sequence is a Geometric Progression $(G.P.)$ where the first term $a = 1$ and the common ratio $r = \frac{-1}{1} = -1$.The formula for t

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(B) The given sequence is a Geometric Progression $(G.P.)$ where the first term $a = 1$ and the common ratio $r = \frac{-1}{1} = -1$.The formula for the $n^{th}$ term of a $G.P.$ is given by $a_n = a \cdot r^{n-1}$.To find the $20^{th}$ term $(n = 20)$:$a_{20} = 1 \cdot (-1)^{20-1}$$a_{20} = 1 \cdot (-1)^{19}$Since $19$ is an odd number,$(-1)^{19} = -1$.Therefore,$a_{20} = 1 \cdot (-1) = -1$.

Write down the $20^{th}$ term of the $G.P. 1, -1, 1, -1, \ldots$

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