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प्रश्न
What will be the 6th, 12th and 25th term of the sequence defined by an = (n – 2)2 + 2n?
उत्तर
Given: an = (n – 2)2 + 2n
To find the 6th term, put n = 6
∴ a6 = (6 – 2)2 + 2(4)
= (4)2 + 12
= 16 + 12
= 28
To find the 12th term, put n = 12
∴ a12 = (12 – 2)2 + 2(12)
= (10)2 + 24
= 100 + 24
= 124
To find the 25th term, put n = 25
∴ a25 = (25 – 2)2 + 2(25)
= (23)2 + 50
= 529 + 50
= 579
Hence, the 6th, 12th and 25th term of the sequence are 28, 124 and 579 respectively.
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