ExamBro
ExamBro
JEE Mains · Maths · STD 11 - 4.1 complex nubers

माना \(\left(-2-\frac{1}{3} i\right)^{3}=\frac{x+i y}{27}(i=\sqrt{-1})\), जहाँ \(x\) तथा \(y\) वास्तविक संख्यायें हैं, तो \(y - x\) बराबर है

  1. A \(91\)
  2. B \(-85\)
  3. C \(85\)
  4. D \(-91\)
Verified Solution

Answer & Solution

Correct Answer

(A) \(91\)

Step-by-step Solution

Detailed explanation

\(\left(-2-\frac{i}{3}\right)^{3}=\left(\frac{x+i y}{27}\right)\) \((-1)^{3}\left(2^{3}+\frac{i^{3}}{27}+3(2) \frac{i^{2}}{9}+3(2)^{2} \cdot \frac{i}{3}\right)=\frac{x-i y}{27}\) \(-\left[8-\frac{i}{27}-\frac{2}{3}+4 i\right]=\frac{x+i y}{27}\)…
Same subject
Explore more questions on app
From JEE Mains
Explore more questions on app