If x = cosθ + i sinθ then the value of xn + 1/xn is
2 cos n θ
2 i sin n θ
2 sin n θ
2 i cos n θ
If ω is a cube root of unity, then arg (ω + ω2) =
π/2
π
π/4
π/3
If n is any integer,then (i)n is
i
1,-1
i,-i
1,-1,i,-i
The principal value of the amplitude of (1 + i) is
3π/4
If the amplitude of a complex number is π/2, then the number is
Purely imaginary
Purely real
0
Neither real nor imaginary
If -i + 3 is a root of x2 - 6x + k = 0 then the value of k is
5
√5
√10
10
8
6
none of these
The principal value of argument of 1 + i is
Which one of the following is correct?
2 + 3i > 1 + 4i
b + 2i > 3 + 2i
12 + 8i > 8 + 12i
None of these
Given x2 + 2 = 0, then x =
2
√2
±√2 i
-2i