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In a given sequence of integers A(n)=A(n-1)-A(n-2) , where A(n) is the nth term in the sequence, n is an integer and n>=3, A(1)=1,A(2)=1. Calculate S(1000), where S(1000) is the sum of first 1000 terms
(1)2
(2)3
(3)4
(4)0
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- Its answer must be 1
bcoz series is like 1,1,0,-1,-1,0,1,1,0,-1,-1,0,.....
sum of 996 numbers are 0
remaining series after 996 numbers are 1,1,0,-1
its sum is 1 - 11 years agoHelpfull: Yes(39) No(5)
- its answer must be zero
bcoz series is like 1,1,0,-1,-1,....
considering this sum of 1000 number will be zero - 11 years agoHelpfull: Yes(6) No(5)
- the series will like as 1,1,0,-1,-1,0,1,1.....the series is repeating with 6 elements.the sum of every 6 element will be 0.and there are 166 group of 6 element their sum will be zero & remaining 4 element will produce the equals 1
- 11 years agoHelpfull: Yes(4) No(0)
- ans : 0;
the pattern of sequence is 0,-1,-1,0,1,1 (with sequence starting from n>=3) which repeats after every 6 terms,and sum of each set=0.
so in the sequence of 1000 terms there are 166 sets of 6 elements,so total sum of first 996 elements is 0 (covering 996 elements).
last 4 elements of first 1000 will be 0,-1,-1,0 with sum = 0.
thus ans. is : 0. - 11 years agoHelpfull: Yes(2) No(3)
- ans is 3
a(3)=0
a(4)=-1
a(5)=1
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.a(10)=1
hence s(1000)=a(1)+a(2)+a(1000)=1+1+1=3 - 11 years agoHelpfull: Yes(1) No(6)
- ans :-2;
the pattern of sequence is 0,-1,-1,0,1,1 (important: as sequence starting from n>=3 so A(1) & A(2) not in sequence). Pattern repeats after every 6 terms,and sum of each set=0.
so in the sequence of 1000 terms there are 166 sets of 6 elements,so total sum of first 996 elements is 0 (covering 996 elements).
last 4 elements of first 1000 will be 0,-1,-1,0 with sum = -2.
thus ans. is :-2.
[mistake in que. is of -ve sign before 2] - 11 years agoHelpfull: Yes(1) No(3)
- 1+1+0+(-1)=1
- 11 years agoHelpfull: Yes(0) No(1)
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