The complex numbers $\sin x + i\cos 2x\;{\rm{and}}\cos x - i\sin 2x\;$ are conjugate to each other for

$x = \left( {n + \frac{1}{2}} \right)\pi $

JEE MATHEMATICS MCQ: COMPLEX NUMBERS

1 Easy

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Analyzing +4 | -1

The complex numbers

\sin x + i\cos 2x\;\mathrm{and}\cos x - i\sin 2x\;

are conjugate to each other for

View answer and explanation

Correct option: D

No value of

x

Option D (0) is correct because after solving the logarithmic equation, the solution x=2 is extraneous.

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{\left| {1 - i} \right|^x} = {2^x}

|z|=1

z \neq \pm 1

z, \frac{z}{1-z^2}

\left|z_r-r\right| \leq r, \forall r=1,2,3, \ldots, n

\left|\sum\limits_{r=1}^n z_r\right|

(z+a b)^3=a^3

a \neq 0

\alpha, \beta

\gamma

|\alpha-\beta|

{z^2} + {\left| z \right|^2} = 0,

z \in C

2x = - 1 + \sqrt 3 i

{\left( {1 - {x^2} + x} \right)^6} - {\left( {1 - x + {x^2}} \right)^6}