For each positive integer,the quantity [size=150]S[/size]n i

For each positive integer,the quantityS n is defined such thatSn+2=(S n)^2- S (n+1).in addition,S 2=1.then which of the following must be true.

a) S 4+S 3+1 =0
b) (S 1) 2 +S +2 0
c) ifS 1=-1 thenS 4 is also equal to-1 .
d) ifS 4 =-7 thenS 1=-2. e) ifS 1 =-3 thenS 4= -7
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