हिंदी

Express the Following Complex Number in the Standard Form a + I B: ( 1 + 2 I ) − 3

Advertisements
Advertisements

प्रश्न

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

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

Advertisements

उत्तर

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

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

\[ = \frac{1}{1 + 8 i^3 + 6i + 12 i^2}\]

\[ = \frac{1}{1 - 8i + 6i - 12} \left( \because i^2 = - 1 \text { & }  i^3 = - i \right)\]

\[ = \frac{1}{- 2i - 11}\]

\[ = \frac{1}{- 2i - 11} \times \frac{- 2i + 11}{- 2i + 11}\]

\[ = \frac{- 2i + 11}{4 i^2 - 121}\]

\[ = \frac{- 2i + 11}{- 4 - 121}\]

\[ = \frac{- 2i + 11}{- 125}\]

\[ = - \frac{11}{125} + \frac{2i}{125}\]

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 13: Complex Numbers - Exercise 13.2 [पृष्ठ ३१]

APPEARS IN

आर.डी. शर्मा Mathematics [English] Class 11
अध्याय 13 Complex Numbers
Exercise 13.2 | Q 1.09 | पृष्ठ ३१

वीडियो ट्यूटोरियलVIEW ALL [1]

संबंधित प्रश्न

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


Express the given complex number in the form a + ib: `(1/5 + i 2/5) - (4 + i 5/2)`


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


Evaluate the following:

(ii) i528


Evaluate the following:

\[i^{37} + \frac{1}{i^{67}}\].


Evaluate the following:

 \[i^{30} + i^{40} + i^{60}\]


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

\[\frac{1 - i}{1 + i}\]


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

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


If \[z_1 = 2 - i, z_2 = 1 + i,\text {  find } \left| \frac{z_1 + z_2 + 1}{z_1 - z_2 + i} \right|\]


Evaluate the following:

\[2 x^3 + 2 x^2 - 7x + 72, \text { when } x = \frac{3 - 5i}{2}\]


Evaluate the following:

\[x^4 + 4 x^3 + 6 x^2 + 4x + 9, \text { when } x = - 1 + i\sqrt{2}\]


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 \[\left( 1 + i \right)z = \left( 1 - i \right) \bar{z}\],then show that \[z = - i \bar{z}\].


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


What is the smallest positive integer n for which \[\left( 1 + i \right)^{2n} = \left( 1 - i \right)^{2n}\] ?


If z1z2z3 are complex numbers such that \[\left| z_1 \right| = \left| z_2 \right| = \left| z_3 \right| = \left| \frac{1}{z_1} + \frac{1}{z_2} + \frac{1}{z_3} \right| = 1\] then find the value of \[\left| z_1 + z_2 + z_3 \right|\] .


Write (i25)3 in polar form.


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


Write −1 + \[\sqrt{3}\] in polar form .


Find the principal argument of \[\left( 1 + i\sqrt{3} \right)^2\] .


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


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


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


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


If \[z = \frac{1 + 7i}{(2 - i )^2}\] , then


If \[z = a + ib\]  lies in third quadrant, then \[\frac{\bar{z}}{z}\] also lies in third quadrant if


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


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


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


Evaluate the following : i–888 


State True or False for the following:

The order relation is defined on the set of complex numbers.


State True or False for the following:

2 is not a complex number.


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


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×