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

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

0.25 is ______

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

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

i is equal

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

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

• 
  
  
  A
• 
  B
• 
  C
• 
  D

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

Gooch crucible is made of :

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

The set { 1 , -1} is closed w.r.t.

• Addition A
• Multiplications B
• Subtraction C
• None of these D

• A prime number A
• An integer B
• A whole number C
• An irrational number D

The negative square root of 9 can be written as:

• -√9 A
• √9 B
• √18 C
• -√18 D

Multiplicative inverse of 0 is

• 0 A
• 1 B
• ±1 C
• Does not exist D

The identity element with respect to subtraction is

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

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

• One A
• Two B
• Three C
• Four D

If z₁ =√-36 ,z₂ =√-25,z3 =√-16 then

• 15 A
• 15i B
• -15i C
• -15 D

Name the property used in 100 + 0 = 100

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

∀x,y∈ R and x < 0, y < 0, which one is true 

• xy < o A
• xy = o B
• xy > o C
• None of these D

In R the left cancellation property w.r.t addition is

• 
  A
• 
  B
• 
  C
• 
  D

• 
  A
• 
  B
• 
  C

• 
  A
• 
  B
• 
  C
• 
  D

6 is

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

• 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

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

For any real numbers x,y,xy=o ⇒

• x ≠ 0 ∧ y ≠ 0 A
• x = 0 ∨ y = 0 B
• x = 0 C
• y = 0 D

i³ =

• -1 A
• i B
• -i C
• 1 D

In R, the additive identity is

• 0 A
• 1 B
• -1 C
• None D

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

• √3 i A
• √7 B
• -2-i C
• √5 D

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