ECAT Pre Engineering MCQ Test With Answer for Chapter 1 Mathematics

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

∀ z ∈ C, multipliucative is

• (1,1) A
• (1,0) B
• (0,1) C
• None of these D

What is the conjugate of -6 -i

• -6 +i A
• 6 + i B
• -6 -i C
• 6 -i D

• 
  A
• 
  B
• 
  C
• 
  D

If a set S contains n elements then P (S) has ........ number of elements

• 2ⁿ A
• 2ⁿ² B
• 2.n C
• n² D

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

If a > b or a < b than a = b is a

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

Associative law of multiplication

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

• 
  A
• 
  B
• 
  C
• 
  D

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

• One A
• Two B
• Three C
• Four D

Q∪ Q' =

• Q A
• Q' B
• N C
• R D

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

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

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

∀x,y∈R and x> 0 , y>0, if x > y

• 
  A
• 
  B
• 
  C
• None of these D

∀ a ε R ∃ o ε R such that a + v = 0 + a = a is property of

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

The set of natural no. is closed under

• multiplication A
• subtraction B
• difference C
• division D

• 
  A
• 
  B
• 
  C
• 
  D

• 
  A
• 
  B
• 
  C
• 
  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

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

• 
  A
• 
  B
• 
  C
• 
  D

What is the conjugate of -7 -2i?

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

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

• √5 A
• √7 B
• -1-2i C
• √3 D

In (x +iy) y is called as

• Imaginary part A
• Complex number B
• Real part C
• None of above D

If in a set of real no a is multiplicative identity then

• a,a = a² A
• a,a = 1 B
• a,a = 0 C
• None of these D

Any recurring decimal represents a

• Irrational no A
• Integer B
• Rational no C
• None of these D

Name the property used in 4.1 + (-4.1) = 0

• Additive inverse A
• Multiplication inverse B
• Additive identity C
• Multiplication identity D

• 
  A
• 
  B
• 
  C
• 
  D

• 
  A
• 
  B
• 
  C
• 
  D

3/2 is

• An irrational number A
• Whole number B
• A positive integer C
• A rational number D

a >b, b >c ⇒a >c is a

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