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प्रश्न
If tn = 2n – 5 is the nth term of an A.P., then find its first five terms
उत्तर
tn = 2n – 5 ......[Given]
∴ t1 = 2(1) – 5 = 2 – 5 = – 3
t2 = 2(2) – 5 = 4 – 5 = – 1
t3 = 2(3) – 5 = 6 – 5 = 1
t4 = 2(4) – 5 = 8 – 5 = 3
t5 = 2(5) – 5 = 10 – 5 = 5
∴ The first five terms of A.P. are – 3, – 1, 1, 3, 5.
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