English

Answer the following: Simplify the following and express in the form a + ib: (1+2i)(3+4i)(5+i)-1

Advertisements
Advertisements

Question

Answer the following:

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

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

Sum
Advertisements

Solution

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

= `(("i" + 2))/"i".((3"i" + 4))/"i". 1/(5 + "i")`

= `(3"i"^2 + 4"i" + 6"i" + 8)/("i"^2(5 + "i"))`

= `(-3 + 10"i" + 8)/(-1(5 + "i"))`  ...[∵ i2 = – 1]

= `((5 + 10"i"))/(-(5 + "i")`

= `((5 + 10"i")(5 - "i"))/(-(5 + "i")(5 - "i"))`

= `(25 - 5"i" + 50"i" - 10"i"^2)/(-(25 - "i"^2)`

= `(25 + 45"i" - 10(-1))/(-[25 - (-1)]`

= `(35 + 45"i")/(-26)`

= `(-35)/26 - 45/26"i"`

shaalaa.com
  Is there an error in this question or solution?
Chapter 1: Complex Numbers - Miscellaneous Exercise 1.2 [Page 21]

APPEARS IN

Balbharati Mathematics and Statistics (Arts and Science) Part 2 [English] Standard 11 Maharashtra State Board
Chapter 1 Complex Numbers
Miscellaneous Exercise 1.2 | Q II. (1) (vii) | Page 21

RELATED QUESTIONS

If α and β are different complex numbers with |β| = 1, then find `|(beta - alpha)/(1-baralphabeta)|`


Find the value of i49 + i68 + i89 + i110 


Find the value of: x3 –  x2 + x + 46, if x = 2 + 3i


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

`3 + sqrt(-64)`


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

(2i3)2 


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


Write the conjugates of the following complex number:

3 – i


Write the conjugates of the following complex number:

cosθ + i sinθ


Find the value of i + i2 + i3 + i4 


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


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

`(x+ 1)/(1 + "i") + (y - 1)/(1 - "i")` = i


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")`


Answer the following:

Solve the following equation for x, y ∈ R:

`(x + "i"y)/(2 + 3"i")` = 7 – i


Answer the following:

Evaluate: (1 − i + i2)−15 


Answer the following:

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


The value of (2 + i)3 × (2 – i)3 is ______.


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


State true or false for the following:

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


What is the smallest positive integer n, for which (1 + i)2n = (1 – i)2n?


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


If the complex number z = x + iy satisfies the condition |z + 1| = 1, then z lies on ______.


If z = x + iy, then show that `z  barz + 2(z + barz) + b` = 0, where b ∈ R, represents a circle.


If |z1| = |z2| = ... = |zn| = 1, then show that |z1 + z2 + z3 + ... + zn| = `|1/z_1 + 1/z_2 + 1/z_3 + ... + 1/z_n|`.


If |z + 4| ≤ 3, then the greatest and least values of |z + 1| are ______ and ______.


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


Which of the following is correct for any two complex numbers z1 and z2?


The point represented by the complex number 2 – i is rotated about origin through an angle `pi/2` in the clockwise direction, the new position of point is ______.


If z is a complex number, then ______.


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


If z1, z2, z3 are complex numbers such that |z1| = |z2| = |z3| = `|1/z_1 + 1/z_2 + 1/z_3|` = 1, then |z1 + z2 + z3| is ______.


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


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)`


i2 + i3 + ... + i4000 =


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×