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

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

• 15 A
• 15 i B
• -15 i C
• -15 D

A prime number can be a factor of a square only if it occurs in the square at least

• Once A
• Thirce B
• Twice C
• None of these D

Associative law of multiplication

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

Gooch crucible is made of :

• Brass. A
• Porcelain. B
• Bronze. C
• Gold. D

• Closure law of addition A
• Associative law of addition B
• Commutative law of multiplication C
• Associative law of multiplication D

√-1 b=

• b A
• 2 B
• 2b C
• None of these D

The additive inverse of 2/3 is

• 3/2 A
• -2/3 B
• -3/2 C
• 0 D

If z = (x,y) , then  z ̅  =

• (-x,y) A
• (x,-y) B
• (-x, -y) C
• None of these D

If A = {x / x ∈ R ∧ x² - 16 = 0} then A =

• - x A
• Infinite set B
• Φ C
• {-4,4} D

Additive inverse of - a - b is

• a A
• -a + b B
• a - b C
• a + b D

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

For each real number, there is a number which is its

• Negative A
• Possitive B
• Opposite C
• Similar D

√25 is a number

• Rational A
• Irrational B
• Natural C
• Odd D

• 
  A
• 
  B
• 
  C
• 
  D

i¹⁰¹ =

• i A
• i² B
• -i C
• -1 D

The additive inverse of 0 is

• 1 A
• -1 B
• 0 C
• Does not exist D

a >b ⇒a +c >b +c is known as

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

A subset of set of complex number whose elements are of the form (a,0) is called

• Real number A
• Complex number B
• Rational number C
• Irrational number D

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

• 1 A
• i B
• -1 C
• -i D

If a and b are real numbers then a+b is also real number this law is called

• associative law of addition A
• closure law of addition B
• Distributive law of addition C
• Commutative law of addition D

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

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

If z₁ = (a,b), z₂=(c,d), then z₁ z₂ = -------------------

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

Every natural number is

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

√x = ______ if is a prime number

• Rational no A
• Natural no B
• Irrational no C
• Complex no D

The property used in -3 <-2 ⇒0 <1

• Commutative property A
• Additive property of inequality B
• Additive inverse C
• Additive identity D

What is the conjugate of -7 -2i ?

• -7 + 2i A
• 7 +2i B
• 7 -2i C
• √53 D

In R the number of identity elements w.r.t.'.' is

• One A
• Two B
• Three C
• Four D

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

• 
  A
• 
  B
• 
  C
• 
  D

Which of the following sets has closure property w.r.t. addition

• { 0 } A
• { 1 } B
• { 0, -1} C
• { 1, -1} D