Q7 of 8 Page 180

If a, b, c are in A.P., then prove that, are in A.P.

Since a, b, c are in AP


⇒ 2b = a + c


ATQ, are in AP



Taking L.C.M and cross multiplying we get,


⇒ 2 (abc) = (a + c) ca


⇒ 2b = a + c


Which is true iff a, b, c are in AP.


Hence, Proved.


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