The sum of first two terms is the 3rd term
Ex: 2,3,5,7,8,15,11,7,
Answers
Answer:
Page No 61:
Question 1:
Which of the following sequences are A.P. ? If they are A.P. find the common difference .
(1) 2, 4, 6, 8,....
(2) 2,
5
2
, 3,
7
3
,....
(3) –10, –6, –2, 2...
(4) 0.3, 0.33, 0.333,...
(5) 0, –4, –8, –12,...
(6) -
1
5
,-
1
5
,-
1
5
,...
(7) 3, 3+
√
2
, 3+2
√
2
, 3+3
√
2
(8) 127, 132, 137,...
ANSWER:
(1) 2, 4, 6, 8,....
The given sequence is an A.P.
Common difference = Second term − First term
= 4 − 2
= 2
(2) 2,
5
2
, 3,
7
3
,....
The given sequence is not an A.P.
(3) –10, –6, –2, 2...
The given sequence is an A.P.
Common difference = Second term − First term
= (−6) − (−10)
= 4
(4) 0.3, 0.33, 0.333,...
The given sequence is not an A.P.
(5) 0, –4, –8, –12,...
The given sequence is an A.P.
Common difference = Second term − First term
= (−4) − (0)
= −4
(6) -
1
5
,-
1
5
,-
1
5
,...
The given sequence is an A.P.
Common difference = Second term − First term
= (−
1
5
) − (−
1
5
)
= 0
(7) 3, 3+
√
2
, 3+2
√
2
, 3+3
√
2
The given sequence is an A.P.
Common difference = Second term − First term
= 3+
√
2
-3
=
√
2
Answer:
- this might help you
- I thick it is ok
