English

Write 1 − I in Polar Form. - Mathematics

Advertisements
Advertisements

Question

Write 1 − i in polar form.

Solution

\[z = 1 - i \]

\[r = \left| z \right|\]

\[ = \sqrt{1 + 1}\]

\[ = \sqrt{2}\]

\[\text { Let } \tan \alpha = \left| \frac{Im\left( z \right)}{Re\left( z \right)} \right|\]

\[ \therefore \tan\alpha = \left| \frac{- 1}{1} \right|\]

\[ = \frac{\pi}{4}\]

\[ \Rightarrow \alpha = \frac{\pi}{4}\]

\[\text { Since point  (1, - 1) lies in the fourth quadrant, the argument of z is given by } \]

\[\theta = - \alpha = - \frac{\pi}{4}\]

\[\text { Polar form = } r\left( \cos \theta + i\sin \theta \right) \]

\[ = \sqrt{2}\left\{ \cos\left( - \frac{\pi}{4} \right) + i\sin\left( - \frac{\pi}{4} \right) \right\}\]

\[ = \sqrt{2}\left( \cos\frac{\pi}{4} - i\sin\frac{\pi}{4} \right)\]

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

APPEARS IN

RD Sharma Mathematics [English] Class 11
Chapter 13 Complex Numbers
Exercise 13.5 | Q 7 | Page 62

Video TutorialsVIEW ALL [1]

RELATED QUESTIONS

Express the given complex number in the form a + ib: i9 + i19


Evaluate the following:

i457


Evaluate the following:

 \[\frac{1}{i^{58}}\]


Evaluate the following:

\[\left( i^{41} + \frac{1}{i^{257}} \right)^9\]


Evaluate the following:

\[( i^{77} + i^{70} + i^{87} + i^{414} )^3\]


Evaluate the following:

 \[i^{30} + i^{40} + i^{60}\]


Find the value of the following expression:

\[\frac{i^{592} + i^{590} + i^{588} + i^{586} + i^{584}}{i^{582} + i^{580} + i^{578} + i^{576} + i^{574}}\]


Find the value of the following expression:

(1 + i)6 + (1 − i)3


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

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


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

\[\left( \frac{1}{1 - 4i} - \frac{2}{1 + i} \right)\left( \frac{3 - 4i}{5 + i} \right)\]


Find the real value of x and y, if

\[(x + iy)(2 - 3i) = 4 + i\]


Find the real values of θ for which the complex number \[\frac{1 + i cos\theta}{1 - 2i cos\theta}\]  is purely real.


Evaluate the following:

\[x^6 + x^4 + x^2 + 1, \text { when }x = \frac{1 + i}{\sqrt{2}}\]


For a positive integer n, find the value of \[(1 - i )^n \left( 1 - \frac{1}{i} \right)^n\].


If \[\frac{z - 1}{z + 1}\] is purely imaginary number (\[z \neq - 1\]), find the value of \[\left| z \right|\].


Write (i25)3 in polar form.


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


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 \[z_1 = - \bar{{z_2}}\].


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


If \[z = \frac{1}{1 - cos\theta - i sin\theta}\] then Re (z) =


If \[x + iy = \frac{3 + 5i}{7 - 6i},\]  then y =


The value of \[(1 + i )^4 + (1 - i )^4\] is


Which of the following is correct for any two complex numbers z1 and z2?

 


Find a and b if a + 2b + 2ai = 4 + 6i


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


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

`(3 + 2"i")/(2 - 5"i") + (3 -2"i")/(2 + 5"i")`


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))`


Show that `(-1 + sqrt(3)"i")^3` is a real number


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


Evaluate the following : i403 


Evaluate the following : `1/"i"^58`


Match the statements of column A and B.

Column A Column B
(a) The value of 1 + i2 + i4 + i6 + ... i20 is (i) purely imaginary complex number
(b) The value of `i^(-1097)` is (ii) purely real complex number
(c) Conjugate of 1 + i lies in (iii) second quadrant
(d) `(1 + 2i)/(1 - i)` lies in (iv) Fourth quadrant
(e) If a, b, c ∈ R and b2 – 4ac < 0, then
the roots of the equation ax2 + bx + c = 0
are non real (complex) and
(v) may not occur in conjugate pairs
(f) If a, b, c ∈ R and b2 – 4ac > 0, and
b2 – 4ac is a perfect square, then the
roots of the equation ax2 + bx + c = 0
(vi) may occur in conjugate pairs

If `((1 - i)/(1 + i))^100` = a + ib, then find (a, b).


The real value of θ for which the expression `(1 + i cos theta)/(1 - 2i cos theta)` is a real number is ______.


If w is a complex cube-root of unity, then prove the following

(w2 + w − 1)3 = −8


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


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×