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STD 11 - 4.1 complex nubers — JEE STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 ScienceJEESTD 11 - 4.1 complex nubers4 Marks
MCQ
The conjugate of complex number $\frac{{2 - 3i}}{{4 - i}},$ is
  • A
    $\frac{{3i}}{4}$
  • ✓
    $\frac{{11 + 10i}}{{17}}$
  • C
    $\frac{{11 - 10i}}{{17}}$
  • D
    $\frac{{2 + 3i}}{{4i}}$
✓

Answer

Correct option: B.
$\frac{{11 + 10i}}{{17}}$
b
(b) $\frac{{2 - 3i}}{{4 - i}} = \frac{{(2 - 3i)\,(4 + i)}}{{(4 + i)\,(4 - i)}}$$ = \frac{{8 + 3 - 12i + 2i}}{{16 + 1}}$$ = \,\frac{{11 - 10i}}{{17}}$
==> Conjugate $ = \frac{{11 + 10i}}{{17}}$.

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