The GATE Grind

GATE Complex Analysis: Complex Integration and Residues – Previous Year Questions

11 GATE previous year questions on Complex Integration and Residues (Complex Analysis, Mathematics) with answers and explanations, from every paper.

  1. GATE 2021 MA Q56 (2 marks, Numerical answer) – R=z=x+iy:0<x<1,−11π<y<11π, with positively oriented boundary Γ. Evaluate (2 i)-1 ez/(ez-2)\,dz.
  2. GATE 2021 MA Q58 (2 marks, Numerical answer) – Count the zeros with multiplicity of P(z)=3z⁵+2iz²+7iz+1 in 1< z <7.
  3. GATE 2022 MA Q14 (1 mark, Multiple choice) – Evaluate C z100/(z101+1)\,dz, where C is z =2 counterclockwise.
  4. GATE 2022 MA Q29 (1 mark, Numerical answer) – How many zeros, counting multiplicity, does 2z⁷−7z⁵+2z³−z+1 have in z <1?
  5. GATE 2023 MA Q15 (1 mark, Multiple choice) – On z <1 define f(z)=z-25z3+z5/5!-z7/7!+z9/9!-z11/11!. P:f has three zeros counting multiplicity in the unit disk. Q:f has one zero in 1/2< z <1.…
  6. GATE 2023 MA Q43 (2 marks, Multiple select) – Let Ω⊆ℂ be open and connected and contain U= z ≤1/2. Let J consist of analytic f on Ω with sup (z,w∈U) f(z)−f(w) =1. P:some f∈J has f′(0) ≥2. Q:every…
  7. GATE 2024 MA Q12 (1 mark, Multiple choice) – C is the ellipse z−2 + z+2 =8 oriented counterclockwise. Evaluate C z2/(z2-2z+2)\,dz.
  8. GATE 2025 MA Q33 (1 mark, Numerical answer) – I=(2 i)-1 C z/[1-(z3)]\,dz, where C is the positively oriented diamond Re z + Im z =1. Find 120I (integer).
  9. GATE 2025 MA Q63 (2 marks, Numerical answer) – Distinct nonzero real α,β and a polynomial Q of degree <5 define f(z)=[6( z)-6(e2 z-Q(z))]/z6. The source says f “satisfies Morera’s theorem in ℂ∖0”.…
  10. GATE 2026 MA Q38 (2 marks, Multiple choice) – Evaluate (1-z)(3 z+5 z)1-z101\,dz, where Γ is z = 7/9, counterclockwise.
  11. GATE 2026 MA Q59 (2 marks, Numerical answer) – Count zeros, with multiplicity, of z6+5z3+4z+11 in 1 < z < 3 (integer).