If $z=4+i \sqrt{7}$, then value of $z^3-4 z^2-9 z+91$ equals

JEE MATHEMATICS MCQ: COMPLEX NUMBERS

1 Medium

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Application +4 | -1

z=4+i \sqrt{7}

, then value of

z^3-4 z^2-9 z+91

equals

View answer and explanation

Correct option: D

-1

Option D (-1) is correct because after substituting

z=4+i \sqrt{7}

into the expression and simplifying, the result is -1.

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