Q22 of 26 Page 8

Find (x + 1)6 + (x – 1)6. Hence or otherwise evaluate( root 2+1 ) ^6 + ( root 2-1 ) ^6 .

We know that-



Hence






Thus,


Replacing b with -b





Now,





Putting a = x & b = 1 in , we get-




putting x = √2






Hence,

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