Find the modulus of each of the following complex numbers and hence express each of them in polar form: ![]()
Let Z = ![]() + i = r(cosθ + isinθ)
 + i = r(cosθ + isinθ)
Now , separating real and complex part , we get
![]() = rcosθ ……….eq.1
 = rcosθ ……….eq.1
1 = rsinθ …………eq.2
Squaring and adding eq.1 and eq.2, we get
4 = r2
Since r is always a positive no., therefore,
r =2,
hence its modulus is 2.
now, dividing eq.2 by eq.1, we get,
![]()
![]()
Since ![]() ,
 , ![]() and
 and ![]() . therefore the θ lies in first quadrant.
 . therefore the θ lies in first quadrant.
![]() , therefore
 , therefore ![]()
Representing the complex no. in its polar form will be
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