Join the Most Relevant JEE Main 2025 Test Series & get 99+ percentile! Join Now
Search any question & find its solution
Question: Answered & Verified by Expert
If the vertices of a square are \(z_1, z_2, z_3\) and \(z_4\) taken in the anti-clockwise order, then \(z_3=\)
MathematicsComplex NumberWBJEEWBJEE 2023
Options:
  • A \(-i \mathrm{z}_1-(1+i) z_2\)
  • B \(\mathrm{z}_1-(1+\mathrm{i}) \mathrm{z}_2\)
  • C \(z_1+(1+i) z_2\)
  • D \(-i \mathrm{z}_1+(1+\mathrm{i}) \mathrm{z}_2\)
Solution:
2445 Upvotes Verified Answer
The correct answer is: \(-i \mathrm{z}_1+(1+\mathrm{i}) \mathrm{z}_2\)


Hint : In \(\triangle A B C \frac{z_1-z_2}{z_3-z_2}=\left|\frac{z_1-z_2}{z_3-z_2}\right|\mathrm{i}^{\pi / 2}=\left|\frac{z_1-z_2}{z_3-z_2}\right| \cdot i=\frac{A B}{B C} \cdot i=i\)
\(\Rightarrow \mathrm{z}_1-\mathrm{z}_2=\mathrm{i}\left(\mathrm{z}_3-\mathrm{z}_2\right) \Rightarrow-i \mathrm{z}_1+\mathrm{i} \mathrm{z}_2=\mathrm{z}_3-\mathrm{z}_2 \Rightarrow \mathrm{z}_3=-\mathrm{i} \mathrm{z}_1+(\mathrm{i}+1) \mathrm{z}_2=-\mathrm{i} \mathrm{z}_1+(1+\mathrm{i}) \mathrm{z}_2\)

Looking for more such questions to practice?

Download the MARKS App - The ultimate prep app for IIT JEE & NEET with chapter-wise PYQs, revision notes, formula sheets, custom tests & much more.