मराठी

If (x+iy)13 = a + ib, where x, y, a, b ∈ R, show that xa-yb = –2(a2 + b2)

Advertisements
Advertisements

प्रश्न

If `(x + iy)^(1/3)` = a + ib, where x, y, a, b ∈ R, show that `x/a - y/b` = –2(a2 + b2)

बेरीज
Advertisements

उत्तर

`(x + iy)^(1/3)` = a + ib

⇒ x + iy = (a + ib)3

i.e., x + iy = a3 + i3 b3 + 3iab (a + ib)

= a3 – ib3 + i3a2b – 3ab2

= a3 – 3ab2 + i(3a2b – b3)

⇒ x = a3 – 3ab2 and y = 3a2b – b3

Thus `x/a = a^2 - 3b^2` and `y/b = 3a^2 - b^2`

So, `x/a - y/b = a^2 - 3b^2 + b^2`

= `-2a^2 - 2b^2`

= –2(a2 + b2)

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 5: Complex Numbers and Quadratic Equations - Solved Examples [पृष्ठ ७८]

APPEARS IN

एनसीईआरटी एक्झांप्लर Mathematics Exemplar [English] Class 11
पाठ 5 Complex Numbers and Quadratic Equations
Solved Examples | Q 2 | पृष्ठ ७८

व्हिडिओ ट्यूटोरियलVIEW ALL [1]

संबंधित प्रश्‍न

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`.


Find the value of i + i2 + i3 + i4 


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

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


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

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


Write the conjugates of the following complex number:

`-sqrt(-5)`


If x + iy = (a + ib)3, show that `x/"a" + y/"b"` = 4(a2 − b2)


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


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:

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


Solve the following equation for x, y ∈ R:

(4 − 5i)x + (2 + 3i)y = 10 − 7i


Answer the following:

Solve the following equations for x, y ∈ R:

(x + iy) (5 + 6i) = 2 + 3i


Answer the following:

Evaluate: (1 − i + i2)−15 


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


The real value of ‘a’ for which 3i3 – 2ai2 + (1 – a)i + 5 is real is ______.


State true or false for the following:

Multiplication of a non-zero complex number by i rotates it through a right angle in the anti-clockwise direction.


State true or false for the following:

The complex number cosθ + isinθ can be zero for some θ.


State true or false for the following:

The points representing the complex number z for which |z + 1| < |z − 1| lies in the interior of a circle.


State true or false for the following:

If n is a positive integer, then the value of in + (i)n+1 + (i)n+2 + (i)n+3 is 0.


What is the principal value of amplitude of 1 – i?


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


If `((1 + i)/(1 - i))^3 - ((1 - i)/(1 + i))^3` = x + iy, then find (x, y).


If the real part of `(barz + 2)/(barz - 1)` is 4, then show that the locus of the point representing z in the complex plane is a circle.


If `(z - 1)/(z + 1)` is purely imaginary number (z ≠ – 1), then find the value of |z|.


The sum of the series i + i2 + i3 + ... upto 1000 terms is ______.


Multiplicative inverse of 1 + i is ______.


State True or False for the following:

Multiplication of a non-zero complex number by –i rotates the point about origin through a right angle in the anti-clockwise direction.


The real value of α for which the expression `(1 - i sin alpha)/(1 + 2i sin alpha)` is purely real is ______.


If `((1 + i)/(1 - i))^x` = 1, then ______.


A real value of x satisfies the equation `((3 - 4ix)/(3 + 4ix))` = α − iβ (α, β ∈ R) if α2 + β2 = ______.


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


The smallest positive integer n for which `((1 + i)/(1 - i))^n` = –1 is ______.


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

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


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


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 `sqrt(-3) xx sqrt(-6)`


Evaluate the following:

i35


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×