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

The square root of 2i - 20i is

• +-(5 - 2i) A
• +-(5 + 2i) B
• (5 - 2i) C
• None of these D

• 
  A
• 
  B
• 
  C
• 
  D

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

• 
  A
• 
  B
• 
  C
• 
  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

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

• 
  A
• 
  B
• 
  C
• 
  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

The identity element with respect to subtraction is

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

√23 is

• A rational number A
• A irrational number B
• An even integer C
• A factor of 36 D

• 
  A
• 
  B
• 
  C
• 
  D

• 
  A
• 
  B
• 
  C
• 
  D

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

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

• 
  A
• 
  B
• 
  C
• 
  D

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

It is not possible to find the exact value of

• π A
• √9 B
• ∛27 C
• √1 D

3/2 is

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

a.a^-1 = a^-1.a = 1 is a

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

A non-terminating non_recurring decimal represents an

• Irrational no A
• Both a & c B
• Rational no C
• None of these D

In (x + iy) x is the known as

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

Such fraction which can not be written in the form ofp⁄q where p,q and q≠ 0,such fractions are called.

• Fractinal numbers A
• Rational Numbers B
• Even Numbers C
• Whole Numbers D

a.a^-1= a^-1.a = 1 is a

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

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

• a+a = 2a A
• a+a = 1 B
• a+a = 0 C
• None of these D

The square root of 2i - 20i is

• ±(5 - 2i) A
• ±(5+ 2i) B
• (5 - 2i) C
• None of these 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

Every prime number is also

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

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

The multiplicative inverse of -3i is

• 3i A
• -3i B
• -1/3i C
• 1/3 i D

• 
  A
• 
  B
• 
  C
• None of these D

• 
  A
• 
  B
• 
  C
• 
  D