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

• 
  A
• 
  B
• 
  C

The additive identity of real number is

• 1 A
• 2 B
• 1/2 C
• 0 D

Name the property used in 4 + 9 = 9 + 4

• Associative property of addition A
• Commutative property of addition B
• Distributive property C
• Additive identity 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

• Set of whole number A
• Rational Numbers B
• Complex numbers C
• Whole numbers 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

The set of natural no. is closed under

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

• 
  A
• 
  B
• 
  C
• 
  D

(a+bi) - (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

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

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

• Principle of equality of fractions A
• Rule for product of fractions B
• Golden rule of fractions C
• Rule for quotient of fractions D

• real part of z A
• imaginary part of z B
• conjugate of z C
• modulus of z D

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

√(-1b) =?

• b i A
• -i b B
• b2 C
• i√b D

• 
  A
• 
  B
• 
  C
• 
  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

Which element is the additive inverse of (a,b) in Complex numbers

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

• 
  A
• 
  B
• 
  C
• 
  D

Gooch crucible is made of :

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

• 
  A
• 
  B
• 
  C
• 
  D

The polar form of complex number x ≠ I y =

• r cos θ+ r sin θ A
• r cos θ+ is sin θ B
• cos θ+ r sin θ C
• i cos θ+ i sin θ D

1.4142135... is ______

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

O is ______

• A positive integer A
• A negative integer B
• A natural number C
• An integer D

6 is

• A prime integar A
• An irrational number B
• A rational number C
• An odd integer D

• 
  A
• 
  B
• 
  C
• 
  D

The conjugate of √5 i is

• √5 A
• -√5 i B
• i C
• 5i D

• 
  A
• 
  B
• 
  C
• 
  D

i is equal

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