English

For a positive integer n, find the value of n(1-i)n(1-1i)n - Mathematics

Advertisements
Advertisements

Question

For a positive integer n, find the value of `(1 - i)^n (1 - 1/i)^"n"`

Sum
Advertisements

Solution

We have `(1 - i)^n (1 - 1/i)^"n"`

= `[(1 - i)(1 - 1/i)]^n`

= `[(1 - i) (1 - 1/i xx i/i)]^n`

= `[(1 - i)(1 - i/i^2)]^n`

= `[(1 - i)(1 + i)]^n`  .....`[because i^2 = -1]`

= `[1 - i^2]^n`

= `[1 + 1]^"n"`

= 2n

Hence, `(1 - i)^n (1 - 1/i)^n` = 2n.

shaalaa.com
  Is there an error in this question or solution?
Chapter 5: Complex Numbers and Quadratic Equations - Exercise [Page 91]

APPEARS IN

NCERT Exemplar Mathematics [English] Class 11
Chapter 5 Complex Numbers and Quadratic Equations
Exercise | Q 1 | Page 91

Video TutorialsVIEW ALL [1]

RELATED QUESTIONS

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


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

`3 + sqrt(-64)`


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")`


Find the value of i49 + i68 + i89 + i110 


If (x + iy)3 = y + vi then show that `(y/x + "v"/y)` = 4(x2 – y2)


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

(x + 2y) + (2x − 3y)i + 4i = 5


Answer the following:

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

`3 + sqrt(-64)`


Answer the following:

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

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


Answer the following:

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

`(5 + 7"i")/(4 + 3"i") + (5 + 7"i")/(4 - 3"i")`


Answer the following:

Show that `(1 - 2"i")/(3 - 4"i") + (1 + 2"i")/(3 + 4"i")` is real


Answer the following:

Simplify `[1/(1 - 2"i") + 3/(1 + "i")] [(3 + 4"i")/(2 - 4"i")]`


If |z1| = 1, |z2| = 2, |z3| = 3 and |9z1z2 + 4z1z3 + z2z3| = 12, then the value of |z1 + z2 + z3| is


The argument of the complex number `(4 + 9i)/(13 + 5i)` is ______


Find the value of k if for the complex numbers z1 and z2, `|1 - barz_1z_2|^2 - |z_1 - z_2|^2 = k(1 - |z_1|^2)(1 - |"z"_2|^2)`


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.


What is the reciprocal of `3 + sqrt(7)i`.


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


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


The value of `sqrt(-25) xx sqrt(-9)` is ______.


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


The value of `(z + 3)(barz + 3)` is equivalent to ______.


Let x, y ∈ R, then x + iy is a non-real complex number if ______.


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


`((1 + cosθ + isinθ)/(1 + cosθ - isinθ))^n` = ______.


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


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


If `|(6i, -3i, 1),(4, 3i, -1),(20, 3, i)|` = x + iy, then ______.


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)`


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`


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

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


Show that `(-1 + sqrt3i)^3` is a real number.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×