- Home
- Standard 11
- Mathematics
4-1.Complex numbers
easy
જો $z$ એ સંકર સંખ્યા હોય, તો $(\overline {{z^{ - 1}}} )(\overline z ) = $
A
$1$
B
$-1$
C
$0$
D
એકપણ નહીં.
Solution
(a) Let $z = x + iy,\overline z = x – iy$ and ${z^{ – 1}} = \frac{1}{{x + iy}}$
==> $(\overline {{z^{ – 1}}} ) = \frac{{x + iy}}{{{x^2} + {y^2}}}$; $\therefore $$(\overline {{z^{ – 1}}} )\,\bar z = \frac{{x + iy}}{{{x^2} + {y^2}}}(x – iy) = 1$
Standard 11
Mathematics
