मराठी
महाराष्ट्र राज्य शिक्षण मंडळएचएससी विज्ञान (सामान्य) इयत्ता ११ वी

Express the following in the form of a + ib, a, b∈R i = −1. State the values of a and b: i(4+3i)(1-i) - Mathematics and Statistics

Advertisements
Advertisements

प्रश्न

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

`("i"(4 + 3"i"))/((1 - "i"))`

बेरीज
Advertisements

उत्तर

`("i"(4 + 3"i"))/((1 - "i")) = (4"i" + 3"i"^2)/(1 - "i")`

= `(4"i" - 3)/(1 - "i")`  ...[∵ i2 = – 1]

= `(4"i" - 3)/(1 - "i") xx (1 + "i")/(1 + "i")`

= `(4"i" + 4"i"^2 - 3 - 3"i")/(1 - "i"^2)` 

= `(4"i" - 4 - 3 -3"i")/(1 + 1)`   ...[∵ i2 = – 1]

= `(-7 + "i")/2`

= `(-7)/2 + 1/2"i"`

This is of the form a + bi, where a = `(-7)/2` and b = `1/2`.

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 1: Complex Numbers - Exercise 1.1 [पृष्ठ ६]

APPEARS IN

संबंधित प्रश्‍न

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 – i) – (–1 + i6)


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


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


Evaluate the following:

(ii) i528


Find the value of the following expression:

i30 + i80 + i120


Find the value of the following expression:

i + i2 + i3 + i4


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:

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


Find the real value of x and y, if

\[(3x - 2iy)(2 + i )^2 = 10(1 + i)\]


Find the real value of x and y, if `((1+i)x-2i)/(3+i) + ((2-3i)y+i)/(3-i) = i, xy ∈ R, i = sqrt-1`


Find the real value of x and y, if

\[(1 + i)(x + iy) = 2 - 5i\]


Evaluate the following:

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


Evaluate the following:

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


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 π < θ < 2π and z = 1 + cos θ + i sin θ, then write the value of \[\left| z \right|\] .


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


If \[\frac{\left( a^2 + 1 \right)^2}{2a - i} = x + iy\] find the value of  \[x^2 + y^2\].


Find the real value of a for which \[3 i^3 - 2a i^2 + (1 - a)i + 5\] is real.


If a = cos θ + i sin θ, then \[\frac{1 + a}{1 - a} =\]


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


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


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


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


The value of \[\frac{i^{592} + i^{590} + i^{588} + i^{586} + i^{584}}{i^{582} + i^{580} + i^{578} + i^{576} + i^{574}} - 1\] is 


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


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


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


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


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


Evaluate the following : i403 


Show that 1 + i10 + i20 + i30 is a real number


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)`.


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


Show that `(-1 + sqrt3 "i")^3` is a real number.


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×