English

Find Z, If | Z | = 4 and Arg ( Z ) = 5 π 6 .

Advertisements
Advertisements

Question

Find z, if \[\left| z \right| = 4 \text { and }\arg(z) = \frac{5\pi}{6} .\]

Advertisements

Solution

We know that,

\[z = \left| z \right|\left\{ \cos\left[ \arg(z) \right] + i\sin\left[ \arg(z) \right] \right\}\]

\[ \Rightarrow z = 4\left( \cos\frac{5\pi}{6} + i\sin\frac{5\pi}{6} \right)\]

\[ = 4\left( - \cos\frac{\pi}{6} + i\sin\frac{\pi}{6} \right)\]

\[ = 4\left( - \frac{\sqrt{3}}{2} + \frac{1}{2}i \right)\]

\[ = - 2\sqrt{3} + 2i\]

Thus, 

\[z = - 2\sqrt{3} + 2i\]

shaalaa.com
  Is there an error in this question or solution?
Chapter 13: Complex Numbers - Exercise 13.5 [Page 62]

APPEARS IN

R.D. Sharma Mathematics [English] Class 11
Chapter 13 Complex Numbers
Exercise 13.5 | Q 12 | Page 62

Video TutorialsVIEW ALL [1]

RELATED QUESTIONS

Express the given complex number in the form a + ib: (1 – i) – (–1 + i6)


Express the given complex number in the form a + ib: `(-2 - 1/3 i)^3`


Evaluate the following:

(ii) i528


Evaluate the following:

\[i^{49} + i^{68} + i^{89} + i^{110}\]


Find the value of the following expression:

i30 + i80 + i120


Express the following complex number in the standard form a + i b:

\[\frac{(1 + i)(1 + \sqrt{3}i)}{1 - i}\] .


Find the real value of x and y, if `((1+i)x-2i)/(3+i) + ((2-3i)y+i)/(3-i) = i, xy ∈ R, i = sqrt-1`


Find the multiplicative inverse of the following complex number:

\[(1 + i\sqrt{3} )^2\]


If \[z_1 = 2 - i, z_2 = - 2 + i,\] find 

Im `(1/(z_1overlinez_1))`


If \[x + iy = \frac{a + ib}{a - ib}\] prove that x2 + y2 = 1.


If \[\left| z + 1 \right| = z + 2\left( 1 + i \right)\],find z.


Express the following complex in the form r(cos θ + i sin θ):

 tan α − i


If z1 and z2 are two complex numbers such that \[\left| z_1 \right| = \left| z_2 \right|\] and arg(z1) + arg(z2) = \[\pi\] then show that \[z_1 = - \bar{{z_2}}\].


Write 1 − i in polar form.


If \[\frac{\left( a^2 + 1 \right)^2}{2a - i} = x + iy\] find the value of  \[x^2 + y^2\].


The value of \[(1 + i)(1 + i^2 )(1 + i^3 )(1 + i^4 )\] is.


If\[z = \cos\frac{\pi}{4} + i \sin\frac{\pi}{6}\], then


If a = cos θ + i sin θ, then \[\frac{1 + a}{1 - a} =\]


The least positive integer n such that \[\left( \frac{2i}{1 + i} \right)^n\] is a positive integer, is.

 

The argument of \[\frac{1 - i\sqrt{3}}{1 + i\sqrt{3}}\] is


\[\text { If } z = \frac{1}{(1 - i)(2 + 3i)}, \text { than } \left| z \right| =\]


\[\text { If  }z = 1 - \text { cos }\theta + i \text { sin }\theta, \text { then } \left| z \right| =\]


The amplitude of \[\frac{1}{i}\] is equal to


The amplitude of \[\frac{1 + i\sqrt{3}}{\sqrt{3} + i}\] is 


The complex number z which satisfies the condition \[\left| \frac{i + z}{i - z} \right| = 1\] lies on


Simplify : `sqrt(-16) + 3sqrt(-25) + sqrt(-36) - sqrt(-625)`


Find a and b if (a+b) (2 + i) = b + 1 + (10 + 2a)i


Find a and b if `1/("a" + "ib")` = 3 – 2i


Express the following in the form of a + ib, a, b ∈ R i = `sqrt(−1)`. State the values of a and b:

`(2 + sqrt(-3))/(4 + sqrt(-3))`


Find the value of `(3 + 2/i) (i^6 - i^7) (1 + i^11)`.


Evaluate the following : i888 


Match the statements of Column A and Column B.

Column A Column B
(a) The polar form of `i + sqrt(3)` is  (i) Perpendicular bisector of
segment joining (–2, 0)
and (2, 0).
(b) The amplitude of `-1 + sqrt(-3)` is  (ii) On or outside the circle
having centre at (0, –4)
and radius 3.
(c) If |z + 2| = |z − 2|, then locus of z is (iii) `(2pi)/3`
(d) If |z + 2i| = |z − 2i|, then locus of z is (iv) Perpendicular bisector of
segment joining (0, –2) and (0, 2).
(e) Region represented by |z + 4i| ≥ 3 is  (v) `2(cos  pi/6 + i sin  pi/6)`
(f) Region represented by |z + 4| ≤ 3 is  (vi) On or inside the circle having
centre (–4, 0) and radius 3 units.
(g) Conjugate of `(1 + 2i)/(1 - i)` lies in (vii) First quadrant
(h) Reciprocal of 1 – i lies in (viii) Third quadrant

Find the value of `(i^(592) + i^(590) + i^(588) + i^(586) + i^(584))/(i^(582) + i^(580) + i^(578) + i^(576) + i^(574))`


Show that `(-1+sqrt3i)^3` is a real number.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×