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

The conjugate of √5 i is

• √5 A
• -√5 i B
• i C
• 5i D

The additive inverse of 0 is

• 1 A
• -1 B
• 0 C
• Does not exist D

2/9,5/7∈ R,(2│9)(5│7)=10/63∈R this property is called

• Associative property A
• Identity property B
• Commutative property C
• Closure property w.r.t multiplication 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

The symbol of irrational is

• W A
• N B
• Q C
• Q' D

Any recurring decimal represents a

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

• 
  A
• 
  B
• 
  C
• 
  D

Every real number is

• A complex number A
• A rational number B
• A natural number C
• A prime number D

Name the property used in 4 x (5 x 8) = ( 4 x 5) x 8

• Associative property of addition A
• Associative property of multiplication B
• Additive identity C
• Multiplicative identity D

In (x +iy) y is called as

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

• Principle of equality of fractions A
• Rule for product of fraction B
• Rule for quotient of fraction C

• Principle of equality of Fractions A
• Rule for product of fraction B
• Golden rule of fraction C
• Rule of quotient of Fraction 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

• 
  A
• 
  B
• 
  C
• 
  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

Every whole number is

• A real number A
• An irrational number B
• A prime number C
• A negative integer D

The multiplicative inverse of 1 - 2i is

• 
  A
• 
  B
• 
  C
• 
  D

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

• √5 A
• √7 B
• -1-2i C
• √3 D

• 
  A
• 
  B
• 
  C
• 
  D

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

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

The equation |x + 4| = x has solution

• x = -2 A
• x = 2 B
• x = -4 C
• x = 4 D

• 1 A
• -1 B
• 
  C
• 
  D

The sum of complex number (a,b) and (c,d) is

• 
  A
• 
  B
• 
  C
• 
  D

• 
  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

What is the conjugate of -6 -i

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

Zero is

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

The multiplicative inverse of 4 is

• -4 A
• -1/4 B
• 1/4 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

What is the conjugate of -7 -2i ?

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