English

If | Z − 5 I | = | Z + 5 I | , Then Find the Locus of Z. - Mathematics

Advertisements
Advertisements

Question

If \[\left| z - 5i \right| = \left| z + 5i \right|\] , then find the locus of z.

Solution

\[\left| z - 5i \right| = \left| z + 5i \right|\]

\[ \Rightarrow \left| z - 5i \right|^2 = \left| z + 5i \right|^2 \]

\[ \Rightarrow \left( z - 5i \right)\left( \bar{{z - 5i}} \right) = \left( z + 5i \right)\left( \bar{{z + 5i}} \right) \left[ \because z \bar{z} = \left| z \right|^2 \right]\]

\[ \Rightarrow \left( z - 5i \right)\left( \bar{z} + 5i \right) = \left( z + 5i \right)\left( \bar{z} - 5i \right)\]

\[ \Rightarrow z \bar{z} + 5zi - 5 \bar{z}i - 25 i^2 = z \bar{z} - 5zi + 5 \bar{z}i - 25 i^2 \]

\[ \Rightarrow 5zi + 5zi = 5 \bar{z}i + 5 \bar{z}i\]

\[ \Rightarrow 10zi = 10 \bar{z}i\]

\[ \Rightarrow z = \bar{z}\]

\[ \Rightarrow \text{z is purely real }\]

Hence, the locus of z is real axis.

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 13 | Page 62

Video TutorialsVIEW ALL [1]

RELATED QUESTIONS

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


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)`


Let z1 = 2 – i, z2 = –2 + i. Find `"Im"(1/(z_1barz_1))`


Find the value of the following expression:

i49 + i68 + i89 + i110


Find the value of the following expression:

i5 + i10 + i15


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+ i2 + i4 + i6 + i8 + ... + i20


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

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


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:

\[\frac{5 + \sqrt{2}i}{1 - 2\sqrt{i}}\]


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


If z1 is a complex number other than −1 such that \[\left| z_1 \right| = 1\] and \[z_2 = \frac{z_1 - 1}{z_1 + 1}\] then show that the real parts of z2 is zero.


If n is any positive integer, write the value of \[\frac{i^{4n + 1} - i^{4n - 1}}{2}\].


If \[\left| z + 4 \right| \leq 3\], then find the greatest and least values of \[\left| z + 1 \right|\].


Write the argument of \[\left( 1 + i\sqrt{3} \right)\left( 1 + i \right)\left( \cos\theta + i\sin\theta \right)\].

Disclaimer: There is a misprinting in the question. It should be  \[\left( 1 + i\sqrt{3} \right)\]  instead of \[\left( 1 + \sqrt{3} \right)\].


If `(3+2i sintheta)/(1-2 i sin theta)`is a real number and 0 < θ < 2π, then θ =


If \[z = \frac{- 2}{1 + i\sqrt{3}}\],then the value of arg (z) is


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

 

If z is a non-zero complex number, then \[\left| \frac{\left| z \right|^2}{zz} \right|\] is equal to


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


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


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 \[z = a + ib\]  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


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

 


Simplify : `4sqrt(-4) + 5sqrt(-9) - 3sqrt(-16)`


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))`


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

`(- sqrt(5) + 2sqrt(-4)) + (1 -sqrt(-9)) + (2 + 3"i")(2 - 3"i")`


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


State true or false for the following:

If a complex number coincides with its conjugate, then the number must lie on imaginary axis.


State True or False for the following:

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


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

(w2 + w − 1)3 = −8


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


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×