Explore topic-wise MCQs in Complex Analysis.

This section includes 15 Mcqs, each offering curated multiple-choice questions to sharpen your Complex Analysis knowledge and support exam preparation. Choose a topic below to get started.

1.

Let f(z)=z4+a1z3+a2z2+a3z+a4=0; a1, a2, a3, a4 being real and non-zero. If f has a purely imaginary root, then what is the value of the expression a3/(a1a2)+ a1a4/(a2a3) ?

A. 0
B. 1
C. -2
D. 2
Answer» C. -2
2.

For a∈R, let f(z)=z5-5z+a. Select the correct statement for α satisfying f(α)=0.

A. α has exactly three possible real values for a>4
B. α has exactly one possible real value for a>4
C. α has exactly three possible real values for a<-4
D. α has exactly one possible real value for -4<a<4
Answer» C. α has exactly three possible real values for a<-4
3.

Let f(z)=&vert;1–z&vert;, if zk=cos(2kπ/10)+isin(2kπ/10), then find the value of f(z1)×f(z2)×…×f(z9).

A. 10
B. 15
C. 20
D. 30
Answer» B. 15
4.

Consider a function f(z) of degree two, having real coefficients. If z1 and z2 satisfying f(z1)=f(z2)=0 are such that Re z1=Re z2=0 and if z3 satisfies f(f(z3))=0, then select the correct statement.

A. Re z3=0
B. Im z3=0
C. Re z3×Imz3≠0
D. Re z3=0 and Im z3=0
Answer» D. Re z3=0 and Im z3=0
5.

Let f(z)=&vert;z&vert;2+Re z(2(z+z̅)+3(z-z̅)/2i, the find the maximum value of &vert;z&vert;2/f(z).

A. 1
B. 2
C. 3
D. 4
Answer» C. 3
6.

Find the range of the function defined by f(z)=Re[2iz/(1-z2)].

A. (−∞, 0) &Union; (0, ∞)
B. [2, ∞)
C. (−∞, −1] &Union; [1, ∞)
D. (−∞, 0] &Union; [2, ∞)
Answer» D. (−∞, 0] &Union; [2, ∞)
7.

Let f(z)=2(z+z̅)+3i(z-z̅) and g(z)=&vert;z&vert;. f(z)=2 divides the region g(z)≤6 into two parts. If Q={(2+3i/4), (5/2+3i/4), (1/4-i/4), (1/8+i/4)}, then find the number of elements of Q lying inside the smaller part.

A. 1
B. 2
C. 3
D. 4
Answer» C. 3
8.

Define f(z)=z2+bz−1=0 and g(z)=z2+z+b=0. If there exists α satisfying f(α)=g(α)=0, which of the following cannot be a value of b?

A. √3i
B. -√3i
C. 0
D. √3i/2
Answer» E.
9.

Let f(z)=arg 1/(1 – z), then find the range of f(z) for &vert;z&vert;=1, z≠1.

A. (-∞, π/2)
B. (-π/2, π/2)
C. (-∞, ∞)
D. [0, π/2)
Answer» C. (-∞, ∞)
10.

Let x, y, z be integers, not all simultaneously equal. If ω is a cube root of unity with Im(ω)≠1, and if f(z)=az2+bz+c, then find the range of &vert;f(ω)&vert;.

A. (0, ∞)
B. [1, ∞)
C. (√3/2, ∞)
D. [1/2, ∞)
Answer» C. (√3/2, ∞)
11.

For all complex numbers z satisfying Im(z)≠0, if f(z)=z2+z+1 is a real valued function, then find its range.

A. (-∞, -1]
B. (-∞, 1/3)
C. (-∞, 1/2]
D. (-∞, 3/4)
Answer» E.
12.

Let f(z)=(z2–z–1)7. If α2+α+1=0 and Im(α)>0, then find f(α).

A. 128α
B. -128α
C. 128α2
D. -128α2
Answer» D. -128α2
13.

For the function f(z)=zi, what is the value of &vert;f(ω)&vert;+Arg f(ω), ω being the cube root of unity with Im(ω)>0?

A. e-2π/3
B. e2π/3
C. e-2π/3+2π/3
D. e-2π/3-2π/3
Answer» B. e2π/3
14.

Let f(z)=z+1/z. What will be the definition of this function in polar form?

A. (r+1/r)cosθ+i(r-1/r)sinθ
B. (r-1/r)cosθ+i(r+1/r)sinθ
C. (r+1/r)sinθ+i(r-1/r)cosθ
D. (r+1/r)sinθ+i(r-1/r)cosθ
Answer» B. (r-1/r)cosθ+i(r+1/r)sinθ
15.

Find the domain of the function defined by f(z)=z/(z+z̅).

A. Im(z)≠0
B. Re(z)≠0
C. Im(z)=0
D. Re(z)=0
Answer» C. Im(z)=0