Q8 of 8 Page 180

If , a2, b2, c2 are in A.P then prove that, are also in A.P.

Given, a2, b2, c2 are in AP


⇒ b2 – a2 = c2 – b2 ..(i)


ATQ, are in AP







(T2 –T1) = (T3 –T2)




(b + a)(b – a) = (c – b)(c + b)


b2 – a2 = c2 – b2


Which is true from equation (i)


Hence, Proved.


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