ECAT Pre Engineering MCQ Test With Answer for Chapter 8 Mathematics

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

pth term of an H.P. is qr and qth term is pr then the rth term of the H.P. is

• pqr A
• 1 B
• pq C
• pqr² D

The number of divisors of 1029, 1547 and 122 are in

• A.P. A
• G.P. B
• H.P. 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

If the pth, qth, and rth terms of an A.P. are in G.P:., then the common ratio of the G.P. is

• 
  A
• 
  B
• 
  C
• 
  D

A sequence is a functions whose domain is a subset of the set of

• Natural numbers A
• Real numbers B
• Whole numbers C
• Rational numbers 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

-2, 1, 4, 7,.... is ______

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

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

• 2 A
• -3/2 B
• 1 C
• 0 D

5th term of a G.P. is 2, then the product of first 9 terms is

• 256 A
• 128 B
• 512 C
• None of these D

The sum of an indicated number of terms in a sequence is called

• sequence A
• progression B
• Series C
• Mean D

p, q, r and s are integers. If the A.M. of the roots of x2- px + q2= 0 and G.M. of the roots of x2- rx + s2= 0 are equal, then

• q is an odd integer A
• r is an even integer B
• p is an even integer C
• s is an odd integer D

A number A is called the arithmetic mean between a and b if a, A, b is ______

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

If the domain of sequence is finite set then the sequence is called

• geometric sequence A
• infinite sequence B
• finite sequence C
• arithmetic sequence D

An infinite sequence has no

• nth term A
• Last term B
• Sum 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 three consecutive numbers a,√ab,b are in

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

• 15/23 A
• 7/15 B
• 7/8 C
• 15/7 D

The sixth term of the sequence 1,3,12,60....is

• 1500 A
• 72 B
• 2160 C
• 2520 D

If a₁, r are first term and the common ratio respectively then the sum of an infinite geometric series is

• 
  A
• 
  B
• 
  C
• 
  D

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

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

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 6th term of an arithmetic sequence whose first term is 3 and common difference in zero is

• 18 A
• 6 B
• 3 C
• 0 D

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

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

If 5,7 and 9 are A.Ms between a and b, then a and b is equal to

• 2 and 12 A
• 1 and 10 B
• 3 and 11 C
• -7 and 2 D

The sum of an infinite geometric series exist if

• | r | < 1 A
• | r | > 1 B
• r = 1 C
• r = -1 D

Find the geometric mean between 4 and 16

• 
  A
• 
  B
• 
  C
• 
  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