ECAT Pre Engineering MCQ Test With Answer for Chapter 8 Mathematics

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

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

The common ration of a geometric sequence cannot be

• 0 A
• 1 B
• 2 C
• 3 D

The 31 term of the A.P 5,2,-1.....is

• -82 A
• 82 B
• 85 C
• -85 D

The5thand 13th terms of an A.P are 5 and-3 respectively The first term of the A.P is

• 1 A
• -15 B
• 9 C
• 2 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

Find the geometric mean between 4 and 16

• 
  A
• 
  B
• 
  C
• 
  D

The third term of a G.P. is 4, The product of first five terms is

• 43 A
• 45 B
• 46 C
• None of these D

If a₁, r and a_nare the first term, common ratio and the nth term respectively of a G. P. then a_n=

• a₁rⁿ A
• a₁r^n-1 B
• a₁rⁿ⁺¹ C
• a₁r D

The sum of infinite numbers of terms of an arithmetic series is

• Finite A
• Infinite B
• May or may not finite C
• None of these D

A Series which does not coverage to a Unique sum is called

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

What is the 26th term of the sequence, if its general term is a_{n = (-1)}ⁿ⁺¹

• 2 A
• 26 B
• 27 C
• 1 D

The sum of first 60 natural numbers is

• 1830 A
• 3660 B
• 1640 C
• 1770 D

Sequence also called..............

• Series A
• Function B
• progressions C
• Elements D

For an arithmetic series to be convergent it is necessary that the series has

• Finite terms A
• d<0 B
• Infinite terms C
• None of these D

The third term of the sequence a_n= (-1)^n-1(n-7) is ______

• 8 A
• 4 B
• -4 C
• 8 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

How many term are there in the A.P, in which a₁ = 11 , a_n =68, d=3

• 30 A
• 27 B
• 20 C
• 21 D

if a_{9 =19,a9=31 are the 6th and 9th term of an A.P. and d=4 is the common difference, then 18th term of the sequence is}

• 65 A
• 67 B
• 71 C
• 75 D

An infinite sequence has no

• nth term A
• Last term B
• Sum C
• None of these 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

• 1, 1/2, 0 A
• 1, 2, 1 B
• 1, 2, 3 C
• 1, 2, 0 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

G is geometric mean between a and b if a, G, b is

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

Every term of a G.P. is positive and also every term is the sum of two preceding terms. Then the common ratio of the G.P. is

• 
  A
• 
  B
• 
  C
• 
  D

If 6th term of a series in A.P, is -2 and 8th term is -8, the first term of the serie is

• 13 A
• -13 B
• 18 C
• -10 D

an -an-1,∀n∈N∧n>1 in an A.P is called

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

1 + 2 + 3 + ...... + n = ______

• 
  A
• 
  B
• 
  C
• 
  D

No term of a harmonic sequence can be

• 0 A
• 1 B
• 2 C
• 3 D

Which term of the A.P 5,8,11,24.............is 320

• 104th A
• 106th B
• 105th C
• 64th D

The general term of the A.P. is

• a₁+ (n - 1) d A
• n + (a₁- 1) d B
• d + (n - 1) a₁ C
• None of these D