Q21.If ω be a cube root of 1, then what is the value of (1–ω) (1–ω2) (1–ω4) (1–ω5)?
Correct answer: 9
Q22.What will be the argument of the complex number z = (i - 1)/(e(i π/3))?
Correct answer: 5π/12
Q23.The product of the values of (cos π/6 + i sin π/6)3/2 is
Correct answer: –i
Q24.For a complex number z the value of (z 3) (z 3) is equivalent to–
Correct answer: 2/z 3
Q25.sin icos 2 and c o s c o s c o s c o s θ - i s i n 2 θ - i s i n 2 θ - i s i n 2 θ - i s i n 2 θ are conjugate to each other for:
Correct answer: 1 n 2 2
Q26.If x 1 i 1 1 i
Correct answer: x = 4n
Q27.Let x, y ∈ R, then x + iy is a non-real complex number if–
Correct answer: y ≠ 0
Q28.For a complex number z, the value of sin2 z + cos2 z is:
Correct answer: 1
Q29.For z = x + iy, x > 0, the integral zt 0 e dt is equal to:
Correct answer: 1/z
Q30.If 1 π x + = 2cos, x 5 then 5 5 1 x + x is equal to
Correct answer: –2
Q31.If complex numbers a1, a2, a3........ are in G.P. having common ratio r such that ≠ ∑ ∑ n n 2k-1 2k+2 k=1 k=1 a = a 0 then number of possible values of r is –
Correct answer: 3
Q32.The nth roots of unity can be arranged as-
Correct answer: a geometric procession
Q33.If ω is cube root of unity, then 1 +ω + ω2 + ω3 +........+ ω52, ω ≠1 is equal to –
Correct answer: –ω2
Q34.If ω (≠ 1) is a cube root of unity and () ω 7 1+ = A +B then the value of A2 + B2 is–
Correct answer: 2
Q35.For any complex number z, the minimum value of z +1 + z – 2 is
Correct answer: 3
Q36.If 1, ω, ω2 are the cube roots of unity, then the value of (1 + ω2)(1 + ω4) (1 + ω8)(1 + ω16) is
Correct answer: 1
Q37.If i = –1, then (1 + i)4 – (1 – i)4 is equal to
Correct answer: 0
EnglishUP TGT 2021, 2004 Haryana PGT 2018 KVS PGT 2018 TGT - 1999
Q38.The smallest positive integer n for which n 1+ i = 1 1 – i, is
Correct answer: 4
EnglishUP TGT-2016 (08-03-2019)
Q39.If A+iB = tan (x+iy), then the value of tan 2x is as
Correct answer: 2 2 2A 1- A - B
EnglishUP TGT-2016 (08-03-2019)
Q40.If sin2 (x + iy) = A + iB, then value of A is
Correct answer: () 1 1 cos2xcosh2y 2 −