हिंदी

If ( 1 + I 1 − I ) 3 − ( 1 − I 1 + I ) 3 = X + I Y Find (X, Y).

Advertisements
Advertisements

प्रश्न

If \[\left( \frac{1 + i}{1 - i} \right)^3 - \left( \frac{1 - i}{1 + i} \right)^3 = x + iy\] find (xy).

Advertisements

उत्तर

\[\left( \frac{1 + i}{1 - i} \right) = \frac{1 + i}{1 - i} \times \frac{1 + i}{1 + i}\]

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

\[ = \frac{1^2 + i^2 + 2i}{1 + 1} [ \because i^2 = - 1]\]

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

\[ = \frac{2i}{2}\]

\[ = i . . . . (1)\]

Also,

\[\left( \frac{1 - i}{1 + i} \right) = \frac{1 - i}{1 + i} \times \frac{1 - i}{1 - i}\]

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

\[ = \frac{1^2 + i^2 - 2i}{1 + 1} [ \because i^2 = - 1]\]

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

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

\[ = - i . . . . (2)\]

It is given that,

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

\[ \Rightarrow (i )^3 - ( - i )^3 = x + iy [\text {From (1) and (2)}]\]

\[ \Rightarrow i^3 + i^3 = x + iy\]

\[ \Rightarrow 2 i^3 = x + iy\]

\[ \Rightarrow 0 - 2i = x + iy [ \because i^3 = - i]\]

\[ \Rightarrow x = 0 \text { and } y = - 2\]

Thus, (xy) = (0, −2).

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 13: Complex Numbers - Exercise 13.2 [पृष्ठ ३२]

APPEARS IN

आर.डी. शर्मा Mathematics [English] Class 11
अध्याय 13 Complex Numbers
Exercise 13.2 | Q 12 | पृष्ठ ३२

वीडियो ट्यूटोरियलVIEW ALL [1]

संबंधित प्रश्न

Express the given complex number in the form a + ib: `(5i) (- 3/5 i)`


Express the given complex number in the form a + ib: i–39


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 + i 7/3) + (4 + i 1/3)] -(-4/3 + i)`


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


Let z1 = 2 – i, z2 = –2 + i. Find Re`((z_1z_2)/barz_1)`


Evaluate the following:

i457


Evaluate the following:

 \[i^{30} + i^{40} + i^{60}\]


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

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


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


Find the least positive integral value of n for which  \[\left( \frac{1 + i}{1 - i} \right)^n\] is real.


If \[a = \cos\theta + i\sin\theta\], find the value of \[\frac{1 + a}{1 - a}\].


Evaluate the following:

\[2 x^4 + 5 x^3 + 7 x^2 - x + 41, \text { when } x = - 2 - \sqrt{3}i\]


Solve the system of equations \[\text { Re }\left( z^2 \right) = 0, \left| z \right| = 2\].


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


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

 tan α − i


Write 1 − i in polar form.


Write the least positive integral value of n for which  \[\left( \frac{1 + i}{1 - i} \right)^n\] is real.


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


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.

 

\[(\sqrt{- 2})(\sqrt{- 3})\] is equal to


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


If θ is the amplitude of \[\frac{a + ib}{a - ib}\] , than tan θ =


\[\frac{1 + 2i + 3 i^2}{1 - 2i + 3 i^2}\] equals


If \[f\left( z \right) = \frac{7 - z}{1 - z^2}\] , where \[z = 1 + 2i\] then \[\left| f\left( z \right) \right|\] is


A real value of x satisfies the equation  \[\frac{3 - 4ix}{3 + 4ix} = a - ib (a, b \in \mathbb{R}), if a^2 + b^2 =\]


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


If z is a complex numberthen


Find a and b if abi = 3a − b + 12i


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:

(1 + i)(1 − i)−1 


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

`((2 + "i"))/((3 - "i")(1 + 2"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.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×