Determine the AP whose 3rd term is 5 and the 7th term is 9.

1.	Determine the AP whose 3rd term is 5 and the 7th term is 9.
Answer» We have a₃ = a + (3 – 1) d = a + 2d = 5 .....(1) and a₇ = a + (7 – 1) d = a + 6d = 9 ......(2) Solving the pair of linear equations (1) and (2), we get a = 3, d = 1 Hence, the required AP is 3, 4, 5, 6, 7, . . .

Answer»

We have

a₃ = a + (3 – 1) d = a + 2d = 5 .....(1)

and a₇ = a + (7 – 1) d = a + 6d = 9 ......(2)

Solving the pair of linear equations (1) and (2), we get

a = 3, d = 1

Hence, the required AP is 3, 4, 5, 6, 7, . . .

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