If a, b, c are in G. P, then which of the following is true?
a = bc
b2 = ac
c = ab
a2 = bc
The sum of the series 1 + 1/2 + 1/22 + .......... is __________.
1
1/2
2
None of these
The harmonic mean between a and b is _________.
2ac / ( a + c )
( a + b ) / 2ab
√ab
( a + b ) / ab
The 7th term of H. P 4/3, 3/2, 12/7, ....... is ________.
36/14
48/21
4/5
4
If nth term of the series 1.3 + 3.5 + 5.7 + ...... is _________.
n ( n + 2 )
n ( n + 5 )
( 2n - 1 ) ( 2n + 1 )
2n ( 2n - 1 )
The common difference of the A.P 13, 8, 3, -2, ....... is ______.
5
-5
10
-4
Sum of cubes of first n natural numbers is _______.
12 + 22 + 32 + ............ + 1002 = ?
5050
( 5050 )2
42925
The 10th term of the A.P 13, 8, 3, -2, ......... is _____________.
-32
32
-57
-52
The 7th term of 1/3, 1/7, 1/11, ........... is ____________.
27
0
7/3
1/27
