मराठी

If z is a complex number, then ______.

Advertisements
Advertisements

प्रश्न

If z is a complex number, then ______.

पर्याय

  • |z2| > |z|2

  • |z2| = |z|2

  • |z2| < |z|2

  • |z2| ≥ |z|2 

MCQ
रिकाम्या जागा भरा
Advertisements

उत्तर

If z is a complex number, then |z2| = |z|2.

Explanation:

Let z = x + yi

|z| = |z + yi| and |z|2 = |x + yi|2

⇒ |z|2 = x2 + y2    ......(i)

Now z2 = x2 + y2i2 + 2xyi

z2 = x2 – y2 + 2xyi

|z|2 = `sqrt((x^2 - y^2)^2 + (xy)^2)`

= `sqrt(x^4 + y^4 - 2x^2 y^2 + 4x^2 y^2)`

= `sqrt(x^4 + y^4 + 2x^2 y^2)`

= `sqrt((x^2 + y^2)^2`

So |z2| = x2 + y2 = |z|2

So |z2| = |z|2

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 5: Complex Numbers and Quadratic Equations - Exercise [पृष्ठ ९६]

APPEARS IN

एनसीईआरटी एक्झांप्लर Mathematics Exemplar [English] Class 11
पाठ 5 Complex Numbers and Quadratic Equations
Exercise | Q 46 | पृष्ठ ९६

व्हिडिओ ट्यूटोरियलVIEW ALL [1]

संबंधित प्रश्‍न

Find the multiplicative inverse of the complex number:

4 – 3i


Find the multiplicative inverse of the complex number.

`sqrt5 + 3i`


Find the number of non-zero integral solutions of the equation `|1-i|^x  = 2^x`.


Simplify the following and express in the form a + ib:

`(1 + 2/i)(3 + 4/i)(5 + i)^-1`


Simplify the following and express in the form a + ib:

`(sqrt(5) + sqrt(3)"i")/(sqrt(5) - sqrt(3)"i")`


Simplify the following and express in the form a + ib:

`(3i^5 + 2i^7 + i^9)/(i^6 + 2i^8 + 3i^18)`


Find the value of: x3 – 5x2 + 4x + 8, if x = `10/(3 - "i")`.


Find the value of: x3 – 3x2 + 19x – 20, if x = 1 – 4i


Write the conjugates of the following complex number:

3 + i


Write the conjugates of the following complex number:

`sqrt(2) + sqrt(3)"i"`


Find the value of i + i2 + i3 + i4 


If `("a" + 3"i")/(2+ "ib")` = 1 − i, show that (5a − 7b) = 0


Show that `((sqrt(7) + "i"sqrt(3))/(sqrt(7) - "i"sqrt(3)) + (sqrt(7) - "i"sqrt(3))/(sqrt(7) + "i"sqrt(3)))` is real


Find the value of x and y which satisfy the following equation (x, y∈R).

(x + 2y) + (2x − 3y)i + 4i = 5


Find the value of x and y which satisfy the following equation (x, y ∈ R).

`((x + "i"y))/(2 + 3"i") + (2 + "i")/(2 - 3"i") = 9/13(1 + "i")`


Find the value of x and y which satisfy the following equation (x, y∈R).

If x(1 + 3i) + y(2 − i) − 5 + i3 = 0, find x + y


Answer the following:

Simplify the following and express in the form a + ib:

(2 + 3i)(1 − 4i)


Answer the following:

Simplify the following and express in the form a + ib:

`5/2"i"(-4 - 3"i")`


Answer the following:

Simplify the following and express in the form a + ib:

`(1 + 2/"i")(3 + 4/"i")(5 + "i")^-1`


If z1 = 2 – 4i and z2 = 1 + 2i, then `bar"z"_1 + bar"z"_2` = ______.


Evaluate: (1 + i)6 + (1 – i)3 


State true or false for the following:

If three complex numbers z1, z2 and z3 are in A.P., then they lie on a circle in the complex plane.


1 + i2 + i4 + i6 + ... + i2n is ______.


If `(1 + i)^2/(2 - i)` = x + iy, then find the value of x + y.


Solve the equation |z| = z + 1 + 2i.


If |z1| = 1(z1 ≠ –1) and z2 = `(z_1 - 1)/(z_1 + 1)`, then show that the real part of z2 is zero.


Find the complex number satisfying the equation `z + sqrt(2) |(z + 1)| + i` = 0.


The number `(1 - i)^3/(1 - i^2)` is equal to ______.


Multiplicative inverse of 1 + i is ______.


The complex number z which satisfies the condition `|(i + z)/(i - z)|` = 1 lies on ______.


Let |z| = |z – 3| = |z – 4i|, then the value |2z| is ______.


If `(3 + i)(z + barz) - (2 + i)(z - barz) + 14i` = 0, then `barzz` is equal to ______.


If α, β, γ and a, b, c are complex numbers such that `α/a +  β/b + γ/c` = 1 + i and `a/α +  b/β + c/γ` = 0, then the value of `α^2/a^2 +  β^2/b^2 + γ^2/c^2` is equal to ______.


The complex number z = x + iy which satisfy the equation `|(z - 5i)/(z + 5i)|` = 1, lie on ______.


Simplify the following and express in the form a + ib.

`(3i^5 +2i^7 +i^9)/(i^6 +2i^8 +3i^18)`


Simplify the following and express in the form a+ib.

`(3i^5 + 2i^7 + i^9)/(i^6 + 2i^8 + 3i^18)`


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×