The absolute value of a complex number, a + ib (also called the modulus ) is defined as the distance between the origin (0, 0) and the point (a, b) in the complex plane.
To find the absolute value of a complex number, we have to take square root of the sum of squares of real and part imaginary part respectively.
|a + ib| = √(a2 + b2)
Example 1 :
Find the absolute value of 7 - i.
Solution :
|7 - i| = √[72 + (-1)2]
= √(49 + 1)
= √50
= √(5 x 5 x 2)
= 5√2
Example 2 :
Find the absolute value of -5 - 5i.
Solution :
|-5 - 5i| = √[(-5)2 + (-5)2]
= √(25 + 25)
= √50
= √(5 x 5 x 2)
= 5√2
Example 3 :
Find the absolute value of 3 - 6i.
Solution :
|3 - 6i| = √[32 + (-6)2]
= √(9 + 36)
= √45
= √(3 x 3 x 5)
= 3√5
Example 4 :
Find the absolute value of 10 - 2i.
Solution :
|10 -2i| = √[102 + (-2)2]
= √(100 + 4)
= √104
= √(2 x 2 x 26)
= 2√26
Example 5 :
Find the absolute value of -4 - 8i.
Solution :
|-4 - 8i| = √[(-4)2 + (-8)2]
= √(16 + 64)
= √80
= √(2 x 2 x 2 x 2 x 5)
= 4√5
Example 6 :
Find the absolute value of -4 + 10i.
Solution :
|-4 + 10i| = √[(-4)2 + 102]
= √(16 + 100)
= √116
= √2 x 2 x 29 = 2 √29
Example 7 :
Find the absolute value of 1 - 8i.
Solution :
|1 - 8i| = √[12 + (-8)2]
= √(1 + 64)
= √65
Example 8 :
Find the absolute value of -4 - 3i.
Solution :
|-4 - 3i| = √(-4)2 + (-3)2
= √(16 + 9)
= √25
= 5
Example 9 :
Find the absolute value of -1 + 5i.
Solution :
|-1 + 5i| = √[(-1)2 + 52]
= √(1 + 25)
= √26
Example 10 :
Find the absolute value of 8 - 3i.
Solution :
|8 - 3i| = √[82 + (-3)2]
= √(64 + 9)
= √73
Kindly mail your feedback to v4formath@gmail.com
We always appreciate your feedback.
©All rights reserved. onlinemath4all.com
May 24, 25 09:41 PM
May 24, 25 02:40 AM
May 23, 25 07:42 PM