ECAT Pre Engineering MCQ Test With Answer for Chapter 8 Mathematics

If all members of a sequence are real numbers then it is called

• A.P A
• Real Sequence B
• G.P C
• None of these D

H.M. between 3 and 7 is

• 
  A
• 
  B
• 
  C
• 
  D

If b₁, b₂, b₃, ... are in G.P. with first term unity and common ratio r, then the minimum value of b₁- b₃+ b₅is equal to

• 3/4 A
• 1/4 B
• 1 C
• None of these D

• 2 A
• -3/2 B
• 1 C
• 0 D

For an A.P common difference d

• Can be zero A
• May or may not zero B
• Cannot be zero C
• None of these D

• 15/23 A
• 7/15 B
• 7/8 C
• 15/7 D

The sum of indicated terms of a sequence is called

• Arithmetic series A
• Series B
• Harmonic series C
• None of these D

• 0 A
• 1 B
• 2 C
• 3 D

If a, b, c, d, e, f are in A.P.,then e-c is equal to

• 2(c - a) A
• 2(f - d) B
• 2(d - c) C
• d - c D

If a₁= 3, r = 2, then the nth term of the G.P. is

• 2.3^n-1 A
• 3.2ⁿ B
• 3.2ⁿ⁺¹ C
• 3.2^n-1 D

A function whose domain is a subset of natural numbers is called ______

• Identity function A
• Sequence B
• Onto function C
• Series D

99th term of the series 2 + 7 + 14 + 23 + 34 + ..... is

• 9998 A
• 9999 B
• 10000 C
• None of these D

The 10th common term between the series 3+7+11+....... and 1 + 6 +11 + ....... is

• 191 A
• 193 B
• 211 C
• None of these D

• 
  A
• 
  B
• 
  C
• 
  D

Geometric mean between a and b is

• 
  A
• 
  B
• 
  C
• 
  D

The sum of first twenty odd integers in A.P is

• 400 A
• 397 B
• 404 C
• 408 D

How many numbers are there between 103 and 750 which are divisible by 6

• 125 A
• 107 B
• 108 C
• 113 D

If a₁= a₂= 2, a_n= a_n-1- 1 (n > 2), then a₅is

• 1 A
• 0 B
• -1 C
• -2 D

A Geometric Series is divergent only if

• |r|>1 A
• |r|≥1 B
• |r|=1 C
• None of these D

If #n = (n-5)2 + 5, then find #3 x #4.

• 54 A
• 12 B
• 4 C
• 9 D

• 1/2 A
• 2 B
• 1/4 C
• 4 D

Sum of n terms of a geometric series if | r | < 1 is

• 
  A
• 
  B
• 
  C
• 
  D

The consecutive terms of a progressions are 30, 24, 20. The next term of the progression is

• 
  A
• 
  B
• 
  C
• 
  D

The next term of the sequence 1, 2, 4, 7, 11, ..... is.

• 15 A
• 16 B
• 17 C
• 18 D

The nth term of an A.P., is 12-4n. Its common difference is

• 8 A
• 4 B
• 4 C
• 16 D

3, 6, 12,.... is

• A.P A
• G.P. B
• H.P. C
• None of these D

The formula an = arn-1represents

• nth term of G.P A
• Sum of the first n terms B
• G.M between a and b C
• None of these D

The difference of two consecutive terms of an A.P is called the

• Common difference A
• Common ratio B
• Geometric series C
• Geometric mean D

The sum of n terms of a series is denoted by

• d A
• n B
• S_n C
• a_n D

• 2²- n - 1 A
• 1 - 2^-n B
• n + 2^-n-1 C
• 2ⁿ- 1 D