If y = 1 + x + x2 + x3 + .... then x is equal to
y-1/y
1-y/y
y/a-y
None of these
Geometric mean of 7,72,73,....7n is
7
7n/2
7n
The arithmetic means of first n odd natural number is
n2
2 n
n
3 n
The sum to infinity of the progression 9 - 3 + 1 -1/3 + .... is
9
9/2
27/4
15/2
The product (32) (32)1/6 (32)1/36 ..... is
16
32
64
0
If three numbers a,b,c are in harmonic progression, then which of the following is true?
1/a, b, 1/c are in AP
1/bc, 1/ca, 1/ab are in HP
ab, bc, ca are in HP
a/b, b/c, c/a are in HP
If S is the sum of an infinite GP, the first term a, then the common ratio r is given by
In an arithmetic progression, the 24th term is 100. Then, the sum of the first 47 terms of the arithmetic progression is
2300
2350
2400
4700
If twice the 11th terms of an AP is equal to 7 times its 21st term, then its 25th term is equal to.
24
120
If a, b, c be in arithmetic progression, then the value of (a+2 b - c) (2 b + c - a) (a + 2 b + c) is
16 a b c
4 a b c
8 a b c
3 a b c
