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प्रश्न
In an A.P. if the sum of third and seventh term is zero. Find its 5th term.
उत्तर
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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