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Question
Show that the following sequence is an A.P. Also find the common difference and write 3 more terms in case.
3, −1, −5, −9 ...
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Solution
\[\text { We have }: \]
\[ - 1 - 3 = - 4, \]
\[ - 5 - ( - 1) = - 4, \]
\[ - 9 - ( - 5) = - 4 . . . \]
\[\text { Thus, the sequence is an A . P . with the common difference being} - 4 . \]
\[\text{ The next three terms are as follows }: \]
\[ - 9 - 4 = - 13\]
\[ - 13 - 4 = - 17\]
\[ - 17 - 4 = - 21\]
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