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Question
In an A.P. if the sum of third and seventh term is zero. Find its 5th term.
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Solution
Given, sum of third and seventh term of A.P. is zero.
We know that, nth term of an A.P. is Tn = a + (n – 1)d
∴ T3 + T7 = 0
⇒ a + 2d + a + 6d = 0
⇒ 2a + 8d = 0
⇒ a + 4d = 0
Now, T5 = a + (5 – 1)d
= a + 4d
= 0
Hence, 5th term of A.P. is zero.
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