Question

find the argument of (a)i​

Answer 1

The argument of a complex number is the angle between the real axis and the line segment joining the point representing the complex number and the origin in a complex plane.

Here the given complex number is just i.

In the standard complex number form, we can write i as 0 + 1i, so we get  Re(i) = 0  and  Im(i) = 1.

Thus the point representing the number will be (0, 1).

The line joining the origin (0, 0) and the point (0, 1) will be along the imaginary axis.

Hence the angle between real axis and this line, i.e., the argument of i, will be π/2 radian.

So π/2 radian is the answer.

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