JEE MATHEMATICS MCQ: COMPLEX NUMBERS

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Application +4 | -1

Let

f(x)=x^4+a x^3+b x^2+c x+d

be a polynomial with real coefficients and real zeroes. If

|f(i)|=1

, (where

i=\sqrt{-1}

) then

a+b+c+d

is equal to

View answer and explanation

Correct option: A

Option A (0) is correct because if |f(i)| = 1, all real zeroes must be zero, leading to f(x) = x⁴, and thus a+b+c+d = 0.

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