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Airforce Group X 4 November 2020 Memory Based Paper

Option 2 : 2

Group X 2021 Full Mock Test

80190

70 Questions
70 Marks
60 Mins

__Concept:__

Modulus of z = |z| = \(\rm \sqrt {x^2+y^2} = \sqrt {Re (z)^2+Im (z)^2}\)

__Calculations:__

Let z = x + iy = -2i

So, x = 0 and y = -2

As we know that if z = x + iy be any complex number, then its modulus is given by, |z| = \(\rm \sqrt{x^2+y^2}\)

∴ |z| = \(\rm \sqrt{(0)^2+{(-2)}^2} = \sqrt 4 = 2\)