Q7 of 37 Page 195

If x3 + y3∝ x3 – y3, let us prove that x + y ∝ x – y.

Given:

x3 + y3∝ x3 - y3




Apply componendo dividend,





Cube root on both sides,




Again apply componendo dividend,




i.e. x + y ∝ x-y


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