Q. 45.0( 3 Votes )

# Find the values of k for which k + 12, k – 6 and 3 are in GP.

Answer :

To find: Value of k

Given: k + 12, k – 6 and 3 are in GP

Formula used: (i) when a,b,c are in GP b^{2} = ac

As, k + 12, k – 6 and 3 are in GP

⇒ (k – 6)^{2} = (k + 12) (3)

⇒ k^{2} – 12k + 36 = 3k + 36

⇒ k^{2} – 15k = 0

⇒ k (k – 15) = 0

⇒ k = 0 , Or k = 15

Ans) We have two values of k as 0 or 15

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