Prove the following identities:


,


R.H.S = 2(a + b + c)2


Applying C1C1 + C2 + C3, we have



Taking, 2(a + b + c) common we get,



Now, applying R2R2 – R1 and R3R3 – R1, we get,



Thus, we have


L.H.S = 2(a + b + c)[1(a + b + c)2]


= 2(a + b + c)3 = R.H.S


Hence, proved.


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