ECAT Pre Engineering MCQ Test With Answer for Chapter 8 Mathematics

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

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

The 26th term of the A.P -2,-4,10,.............is

• 136 A
• -136 B
• 148 C
• -148 D

If p, q, r and in A.P., a is G.M. between p and q and b is G.M. between q and r, then a², q², b²are in

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

Find the sum of the infinite geometric series 2 + 1 + 0.5 + ....

• 3.5 A
• 3 B
• 4 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 formula an = a +(n-1)d for an A.P is called

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

An indicated sum of terms of a sequence is represented by

• Sn A
• an B
• S(n) C
• {Sn} D

If a_n= 2n -3, write the first four terms

• -3, -1, 1, 3 A
• 1, 3, 5, 7 B
• -1, 1, 3, 5 C
• None of these D

The element range of sequence are called

• Series A
• progression B
• Members C
• Terms D

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

No term of a harmonic sequence can be

• 0 A
• 1 B
• 2 C
• 3 D

Let a₁, a₂, a₃, a₄and a₅be such that a₁, a₂, and a₃are in A.P., a₂, a₃and a₄are in G.P and a₃, a₄and a₅are in H.P. Then, a₁, a₃and a₅are in

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

• 12 A
• 13 B
• 14 C
• 15 D

1/2,1/3,1/4,1/5.........is

• a geometric sec A
• an arithmetric series B
• finite sequence C
• an infinite sequece D

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

• 400 A
• 397 B
• 404 C
• 408 D

A Geometric Series is divergent only if

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

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

• 
  A
• 
  B
• 
  C
• 
  D

• 
  A
• 
  B
• 
  C
• 
  D

If x,y are two -ve distinct numbers then

• A>G>H A
• A<G<H B
• A=G=H C
• None of these D

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

• General term A
• Common ratio B
• Common difference C
• None of these D

If three unequal numbers p, q, r are in H.P. and their squares are in A.P., then the ration p : q : r is

• 
  A
• 
  B
• 
  C
• 
  D

The common ration of a geometric sequence cannot be

• 0 A
• 1 B
• 2 C
• 3 D

3, 6, 12,.... is

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

In following question, a number series is given with one term missing. choose the correct alternative that will same pattern and fill in the blank spaces.1 , 4, 9, 16, 25, x

• 35 A
• 36 B
• 48 C
• 49 D

A sequence of number whose reciprocals form an arithmetic sequence is called

• Geometric sequence A
• Arithmetic series B
• Harmonic sequence C
• Harmonic series D

Which one represents a sequence

• an A
• Sn B
• a(n) C
• {an} D

Given two numbers a and b. Let A denote the single A.M. between these and S denote the sum of n A.M.'s between them. Then S/A depends upon

• n, a, b A
• n, a B
• n, b C
• n D

• 15/23 A
• 7/15 B
• 7/8 C
• 15/7 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

For three consecutive terms in A.P middle term is called

• A.M A
• nth term B
• Central term C
• None of these D