NCERT Class XI Mathematics - Complex Numbers and Quadratic Equations - Solutions

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Question : 47
Total: 52
Find the modulus of
1+i
1i
1i
1+i

Solution:  
We have,
1+i
1i
1i
1+i
=
(1+i)2(1i)2
(1i)(1+i)

=
(11+2i)(112i)
1+1
=
2i+2i
2
=
4i
2
= 2i
|
1+i
1i
1i
1+i
|
= 22 = 2
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