wayground logo

Free Printable Worksheets

Font size

S
M
L
XL
Worksheets

complex number

Total questions: 20

Worksheet time: 26mins

Name
Class
Date
1.


 (1)13=?  Choose correct options.\left(-1\right)^{\frac{1}{3}}=?\ \ Choose\ correct\ options.  

a)

-1

b)

 1232i\frac{1}{2}-\frac{\sqrt{3}}{2}i  

c)

 12+32i-\frac{1}{2}+\frac{\sqrt{3}}{2}i  

d)

 12+32i\frac{1}{2}+\frac{\sqrt{3}}{2}i  

e)

 1232i-\frac{1}{2}-\frac{\sqrt{3}}{2}i  

2.

 (3+i)21+i\frac{\left(3+i\right)^2}{1+i}  

a)

7+i

b)

7-i

c)

-7-i

d)

-7+i

3.

Find polar representation of (-1-i)

a)

2(cos π4i sin π4)\sqrt{2}\left(\cos\ \frac{\pi}{4}-i\ \sin\ \frac{\pi}{4}\right)

b)

2(cos π4+i sin π4)\sqrt{2}\left(\cos\ \frac{\pi}{4}+i\ \sin\ \frac{\pi}{4}\right)

c)

2(cos 3π4+i sin 3π4)\sqrt{2}\left(\cos\ \frac{3\pi}{4}+i\ \sin\ \frac{3\pi}{4}\right)

d)

2(cos 3π4i sin 3π4)\sqrt{2}\left(\cos\ \frac{3\pi}{4}-i\ \sin\ \frac{3\pi}{4}\right)

4.

which of the following statement is correct.

a)

i = 2i

b)

i < 2i

c)

i > 2i

d)

can not be compared.

5.

 Find  (1+ww2)3 +(1+w2w)3Find\ \ \left(1+w-w^2\right)^3\ +\left(1+w^2-w\right)^3  

a)

16

b)

-16

c)

0

d)

non of these

6.

 Find (2+3w+3w2)7Find\ \left(2+3w+3w^2\right)^7  

a)

1

b)

0

c)

2

d)

-1

7.

 find 1i17find\ \frac{1}{i^{17}}  

a)

1

b)

i

c)

-i

d)

-1

8.

 choose the correct options  i = ?choose\ the\ correct\ options\ \ \sqrt{i}\ =\ ?  

a)

 12+12i\frac{1}{\sqrt{2}}+\frac{1}{\sqrt{2}}i  

b)

 12+12i-\frac{1}{\sqrt{2}}+\frac{1}{\sqrt{2}}i  

c)

 1212i-\frac{1}{\sqrt{2}}-\frac{1}{\sqrt{2}}i  

d)

 1212i\frac{1}{\sqrt{2}}-\frac{1}{\sqrt{2}}i  

9.

 z+z =?\overline{z}+z\ =?  

a)

2z

b)

2 Re(z)

c)

2i Im(z)

d)

Non of the above

10.

Find the real and imaginary part for reciprocal of 2-3i.

a)

213, 313\frac{2}{13},\ -\frac{3}{13}

b)

213, 313i\frac{2}{13},\ -\frac{3}{13}i

c)

213, 313i\frac{2}{13},\ \frac{3}{13}i

d)

213, 313\frac{2}{13},\ \frac{3}{13}

11.

 z =z        ...................................z\ =\overline{z}\ \ \ \ \ \Longleftrightarrow\ \ \ _{...................................}  

a)

z=0

b)

z is a real number

c)

z is a purely imaginary number.

d)

Non of the above.

12.

 If  z2= 1 thenIf\ \ z^2=\ -1\ then  

a)

 z=±1z=\pm1  

b)

 z=±iz=\pm i  

c)

 z=±(1+i)z=\pm\left(1+i\right)  

d)

Non of the above

13.

 z1+z2  z1+z2\left|z_1+z_2\right|\ \ge\ \left|z_1\right|+\left|z_2\right|  

a)

True

b)

false

14.

Which of the following is the reciprocal of i.

a)

-i

b)

i

c)

1

d)

-1

15.

Conjugate of 2i is

a)

2i

b)

1/2i

c)

-2i

d)

-2

16.

What is the value of r if z= 3 + 5 i

a)

6

b)

34

c)

36

d)

34\sqrt{34}

17.

 Find the principal value of argument for  1232iFind\ the\ principal\ value\ of\ \arg ument\ for\ \ \frac{1}{2}-\frac{\sqrt{3}}{2}i  

a)

 2π3\frac{2\pi}{3}  

b)

 π3\frac{\pi}{3}  

c)

 2π3-\frac{2\pi}{3}  

d)

 π3-\frac{\pi}{3}  

18.

 (i)(4n1)=?\left(-i\right)^{\left(4n-1\right)}=?  

a)

-i

b)

i

c)

1

d)

-1

19.

 If z1 and z2 have arguments 35° and 36°, then the argument of (z1z2 ) isIf\ z_1\ and\ z_2\ have\ \arg uments\ 35\degree\ and\ 36\degree,\ then\ the\ \arg ument\ of\ \left(z_1z_{2\ }\right)\ is  

a)

 35°35\degree  

b)

 71°71\degree  

c)

 36°36\degree  

d)

 1°1\degree  

20.

 Find  w218Find\ \ w^{218}  

a)

0

b)

1

c)

w

d)

 w2w^2