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प्रश्न
If tn = 2n – 5 is the nth term of an A.P., then find its first five terms.
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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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