Mathematics · 2021
JEE Main · 27 July 2021, Shift 2 · Q71
Let C be the set of all complex numbers. Let S_1={z ∈ C:|z-2| ≤ 1} and S_2={z ∈ C: z(1+i)+z̄(1-i) ≥ 4}. Then, the maximum value of |z-5/2|^2 for z ∈…
Let $\displaystyle \mathbb{C}$ be the set of all complex numbers. Let
$$\begin{aligned}
& S_1=\{z \in \mathbb{C}:|z-2| \leq 1\} \text { and } \\
& S_2=\{z \in \mathbb{C}: z(1+i)+\bar{z}(1-i) \geqslant 4\} .
\end{aligned}
$$Then, the maximum value of $\displaystyle \left|z-\frac{5}{2}\right|^2$ for $\displaystyle z \in \mathrm{~S}_1 \cap \mathrm{~S}_2$ is equal to :
Official answer
(4)
$\displaystyle \frac{5+2 \sqrt{2}}{4}$
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JEE Main 2021 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.