ECAT Pre Engineering Mathematic MCQ Test With Answer for Chapter 1 (Number System)

∀a,b ε R, ab = be is a

• Commutative law of multiplication A
• Closure law of multiplication B
• Associative law of multiplication C
• Multiplicative identity 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

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

i² =

• 1 A
• 2 B
• -1 C
• 0 D

• Commutative law of addition A
• Associative law of addition B
• Additive identity C
• Additive inverse D

• (a + b)c = ac + bc A
• a + b = b + a B
• (a + b) + c = a + (b + c) C
• a(b +c) = ab + ac D

• 
  A
• 
  B
• 
  C
• 
  D

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

• additive property A
• multiplicative property B
• additive inverse C
• additive identity D

In R, the multiplicative inverse of a is

• 0 A
• 1 B
• -a C
• 1/a 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

• Closure law of addition A
• Associative law of addition B
• Additive inverse C
• Additive identity D

i^-(4n+2) = -------------------------------

• 1 A
• i B
• -1 C
• -i 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

• N A
• r B
• 2r C
• π D

• 
  A
• 
  B
• 
  C
• 
  D

Decimal part of irrational number is

• Terminating A
• Repeating only B
• Neither repeating nor terminating C
• Repeating and terminating D

The value of x, and y, when (x + iy)²= 5 + 4i

• X = 2, y = -1 A
• X = -2, y=1 B
• X = 2, y = -1 C
• X = 2, y = 2 D

Union of the sets of rational and irrational numbers is called 6th set of

• Natural numbers A
• Real numbers B
• Whole numbers C
• Prime numbers D

The multiplicative inverse of 0 is

• 1 A
• -1 B
• 0 C
• Does not exist D

The additive inverse of 1 is

• 1 A
• -1 B
• 0 C
• Does not exist D

4/√49 is a

• Irrational Number A
• Prime Number B
• Rational number C
• Whole number D

The identity element with respect to subtraction is

• 0 A
• -1 B
• 0 and 1 C
• None of thes D

Every natural number is

• A prime number A
• An irrational number B
• An integer C
• An even number D

• 
  A
• 
  B
• 
  C
• 
  D

If Z₁= 1 + i, Z₂= 2+3i, then |Z₂- Z₁| = ?

• 
  A
• 
  B
• 
  C
• 
  D

• A prime number A
• An integer B
• A whole number C
• An irrational number D

i¹⁰¹=

• i A
• i² B
• -i C
• -1 D

The√ is used for the

• Positive square root A
• Negative square root B
• +ve and -ve square root C
• Whole number D