ECAT Pre General Science MCQ Test With Answer for Mathematics Chapter 1

√x = ______ if is a prime number

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

Every real number is

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

• Commutative property of addition A
• Closure property of addition B
• Additive inverse C
• Associative property w.r.t. to addition D

The set of natural no. is closed under

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

The identity element with respect to subtraction is

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

The square roots of negative numbers is called

• Real no A
• Complex no B
• Positive no C
• Negative no D

What is the conjugate of -6 -i?

• -6 +i A
• 6+i B
• -6 -i C
• 6 -i 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 = -i C
• x = 2, y = 2 D

Gooch crucible is made of :

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

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

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

The multiplicative inverse of 2/3 is

• 3/2 A
• -2/3 B
• -3/2 C
• 1 D

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

• 
  A
• 
  B
• 
  C
• 
  D

• 15 A
• 15 i B
• -15 i C
• -15 D

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

• z is purely imaginary A
• a is any complex number B
• z is real C
• None of these D

Every recurring decimal represents

• A natural number A
• A rational number B
• An irrational number C
• A whole number D

i =

• 
  A
• 
  B
• 
  C
• 
  D

Name the property used in 100 + 0 = 100

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

• 
  A
• 
  B
• 
  C

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

• 1 A
• i B
• -1 C
• -i D

QUQ'

• 
  A
• 
  B
• 
  C
• 
  D

The multiplicative inverse of 1 is

• 1 A
• -1 B
• 0 C
• Does not exist D

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

The equation |x +4| = x has solution

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

• 
  A
• 
  B
• 
  C
• 
  D

If 0 = R, thenthe additive inverse of a is

• 1/9 A
• ^1/-9 B
• a C
• -a D

• 
  A
• 
  B
• 
  C
• 
  D

√-1 b=

• b A
• 2 B
• 2b C
• None of these D

If z₁= 2 + 6i and z₂= 3 + 7i, then which expression defines the product of z₁and z₂?

• 36 + (-32)i A
• -36 + 32i B
• 6 + (-11)1 C
• 0, +(-12)i 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