English

If a + ib = (x+i)22x2+1 prove that a2 + b2 = (x2+1)2(2x+1)2

Advertisements
Advertisements

Question

If a + ib  = `(x + i)^2/(2x^2 + 1)` prove that a2 + b= `(x^2 + 1)^2/(2x + 1)^2`

Sum
Advertisements

Solution

`a + ib  = (x + i)^2/(2x^2 + 1)  ......(1)` 

i के स्थान पर – i रखने से

By replacing i with –i

`a - ib  = (x + i)^2/(2x^2 + 1)  ......(2)` 

समी. (1) और (2) का गुणा करने पर

On multiplying equations (1) and (2)

`(a + ib)(a - ib)  = (x + i)^2/(2x^2 + 1) xx (x - i)^2/(2x^2 + 1)`

or `a^2  -  i^2b^2  =  [(x+i)(x - i)]^2/(2x^2  + 1)^2`

or `a^2 + b^2  = (x^2 - i^2)^2/(2x^2 + 1)^2`

or `a^2 + b^2  = (x^2  + 1)^2/(2x^2 + 1)^2`

shaalaa.com
  Is there an error in this question or solution?
Chapter 4: Complex Numbers and Quadratic Equations - Miscellaneous Exercise [Page 86]

APPEARS IN

NCERT Mathematics [English] Class 11
Chapter 4 Complex Numbers and Quadratic Equations
Miscellaneous Exercise | Q 6. | Page 86

Video TutorialsVIEW ALL [1]

RELATED QUESTIONS

Express the given complex number in the form a + ib: 3(7 + i7) + i(7 + i7)


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 – i)4


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


Evaluate the following:

 \[\frac{1}{i^{58}}\]


Find the value of the following expression:

i5 + i10 + i15


Find the value of the following expression:

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


Express the following complex number in the standard form a + ib:

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


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

\[\frac{2 + 3i}{4 + 5i}\]


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

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


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


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


Evaluate the following:

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


Find the number of solutions of \[z^2 + \left| z \right|^2 = 0\].


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


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


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


For any two complex numbers z1 and z2 and any two real numbers a, b, find the value of \[\left| a z_1 - b z_2 \right|^2 + \left| a z_2 + b z_1 \right|^2\].


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


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


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


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


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


If z is a complex numberthen


If the complex number \[z = x + iy\] satisfies the condition \[\left| z + 1 \right| = 1\], then z lies on


Find a and b if abi = 3a − b + 12i


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:

(1 + i)−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")`


Evaluate the following : i116 


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


Evaluate the following : i30 + i40 + i50 + i60 


If z1 and z2 both satisfy `z + barz = 2|z - 1|` arg`(z_1 - z_2) = pi/4`, then find `"Im" (z_1 + z_2)`.


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

Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×