Find the derivative of the function given by f (x) = (1 + x) (1 + x2) (1 + x4) (1 + x8) and hence find f ′(1).


Given: f (x) = (1 + x) (1 + x2) (1 + x4) (1 + x8)

Taking log on both sides, we get


log f (x) =log (1 + x) + log (1 + x2) + log (1 + x4) + log (1 + x8)


Now, differentiate both sides with respect to x











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