Q7 of 37 Page 195

If a2 + b2∝ ab, let us prove that a + b ∝ a – b.

Given: a2 + b2∝ ab to prove a + b ∝ a-b

a2 + b2= 2kab


as 2k is a constant.


It can be written as:



Apply componendo dividend,




Square root on both sides,



i.e a + b ∝ a-b


hence proved.


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