Mathematics
The nth term of an A.P. is 7n - 5. Its common difference is :
2
9
16
7
AP GP
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Answer
Given,
nth term = 7n - 5
(n - 1)th term = 7(n - 1) - 5 = 7n - 7 - 5
= 7n - 12.
By formula,
d = nth term - (n - 1)th term
= (7n - 5) - (7n - 12)
= 7n - 7n - 5 + 12
= 7.
Hence, Option 4 is the correct option.
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