ECAT Pre General Science MCQ Test With Answer for Mathematics Chapter 1

• A rational number A
• A natural number B
• An irrational number C
• An integer D

Geometrically, the modulus of a complex number represents its distance from the

• Point (1, 0) A
• Point (0, 1) B
• Point (1, 1) C
• Point (0, 0) D

Total number of subsets that can be formed out of the set {a,b,c} is

• 1 A
• 4 B
• 8 C
• 12 D

What is the conjugate of -7 -2i?

• -7 + 2i A
• 7 + 2i B
• 7 -2i C
• None of these D

If Z = (1,2), then Z^-1= ?

• (0.2, 0.4) A
• (-0.2, 0.4) B
• (0.2, -0.4) C
• (-0.2, -0.4) D

Every prime number is also

• Rational number A
• Even number B
• Irrational number C
• Multiple of two numbers D

• a = a A
• a < a B
• a > a C
• a²= a D

1/3 is a decimal

• Recurring A
• Terminating B
• Non-terminating C
• None of the above D

The set {0,-1} hold closure property under

• Addition A
• Both a & c B
• Multiplication C
• None of these D

0.25 is ______

• An irrational number A
• A natural number B
• A prime number C
• A rational number D

• 
  A
• 
  B
• 
  C
• None of these D

Multiplicative inverse of 0 is

• 0 A
• 1 B
• ±1 C
• Does not exist D

The product of complex numbers (a,b) and (c,d) is

• (ac, bd) A
• (ac-bd, ad+bc) B
• (ab,cd) C
• (ac+bd,ad-bc) D

If z₁ =√-36 ,z₂ =√-25,z3 =√-16 then

• 15 A
• 15i B
• -15i C
• -15 D

The multiplicative inverse of 1 - 2i is

• 
  A
• 
  B
• 
  C
• 
  D

Some of two real numbers is also a real number , this property is called:

• Commutative property w.r.t addition A
• Closure property w.r.t. addition B
• Associative property w.r.t. addition C
• Distributive property w.r.t addition D

π is ______

• A complex number A
• A rational number B
• A natural number C
• An irrational number D

(7,9) +(3,-5) =

• (4,4) A
• (10,4) B
• (9,-5) C
• (7,3) D

• Multiplication property A
• Additive property B
• Trichotomy property C
• Transitive property of inequality D

(a,0) x (c,0) =

• (0,ac) A
• (ac,0) B
• (0,0) C
• (a,c) D

(a +bi) -c (c +di) =

• (a +b) = (c +d) A
• (a +c) + i(b +d) B
• (a -c) + (c -d)i C
• (a -c) +(b -d) i D

In R, the multiplicative identity is

• 0 A
• 1 B
• -1 C
• None D

3.5+5.4=5.4+3.5 =8.9 this property of addition is called

• additive identity A
• assoclative property B
• commulative property C
• closure property D

The solution set of the equation |3x + 2| = 5 is

• 
  A
• 
  B
• 
  C
• 
  D

• Commutative law of multiplication A
• Closure law of multiplication B
• Associative law of multiplication C
• Multiplication identity D

• Additive property in R A
• Multiplication property in R B
• Cancellation property in R C
• Distribution property in R D

If z₁= 2 + 6i and z₂= 3 + 7i, then which expression defines the product of z₁and z₂?

• 36 + (-32)i A
• -36 + 32i B
• 6 + (-11)1 C
• 0, +(-12)i D

√2 +√3 +√5) = (√2 +√3 +√5: this property is called

• associative property w.r.t addition A
• commutative property B
• Closure property w.r.t addition C
• Additive identity D

(a,b) +(-a,-b) =

• (0,0) A
• (a,b) B
• (-a,-b) C
• (1,1) D

The symbol of irrational is

• W A
• N B
• Q C
• Q' D