# we know infinite+infinite=infinite but infinite-infinite=not any conclusionor we can say undetermined why?

420 Points
13 years ago

Dear Vinod

You should know that ∞ is not a number its just a symbol. its a symbol for a number which changes very fastly and crosses all the limits. so when we talk about their sum then we can definately say that their sum will also follow the same pattern i.e. it will change very fast and will cross all the limit. but when we talk about the difference then we can not say that in expression

∞ - ∞  which ∞ is bigger as ∞ is not a number one ∞ may be very large compared to other, or they may be compareble so any thing can happen.

hence ∞-∞ will be indeterminate

All the best.

AKASH GOYAL

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Aniket Patra
48 Points
13 years ago

Infinity is not a number rather it is a behavior or tendency of a variable.U can't plot infinity on paper.Now when u add infinity with infiity it is always infinity.But the same thing does not occur for the difference betweeen them.because both may not be same..as for example u take 100000 as infinity and I take 1000 as infinity..Their defference has a value ( in terms infinity)..Again one may take 100 as infinity and another takes 10000000000 as infinity..Their difference is different from the above one..But when u add it is always infinity..