Q22 of 24 Page 115

Determine k so that k2+ 4k + 8, 2k2 + 3k + 6, 3k2 + 4k + 4 are three consecutive terms of an AP.

As, k2+ 4k + 8, 2k2 + 3k + 6, 3k2 + 4k + 4 are three consecutive terms of an AP


Difference between consecutive terms will be equal


⇒ 3rd term – 2nd term = 2nd term – 1st term


⇒ 3k2 + 4k + 4 – 2k2 – 3k – 6 = 2k2 + 3k + 6 – k2 – 4k – 8


⇒ 2k = 0


⇒ k = 0


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