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Question
Find the first term and common difference for the following A.P.:
5, 1, –3, –7, ...
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Solution
5, 1, –3, –7, ...
Here, a = t1 = 5, t2 = 1, t3 = −3, ...
The first term (a) = 5
d = t2 − t1
= 1 − 5
= −4
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