infinity

bla:

b^-2 . (-infinity) = +infinity
why?

Do you mean b^ (-2*-infinity) ? And is b>0 ?

Melody:

bla:

b^-2 . (-infinity) = +infinity
why?

Do you mean b^ (-2*-infinity) ? And is b>0 ?

No, In my math book it says:

b^-N.(-infinity) equals positive infinity.
I don't know how :/

N being natural numbers (1,2,3,4...)

how is n begin with natural Numbers like 1 2 3 4 5 and so on

Hi Bla,
I have graphed
y = b ^-N where N is a natural number.

copy and paste this URL into your browser to see my graph
https://www.desmos.com/calculator/epiuaaghk5

From the graph (and my own logic) this is what I conclude:

If b>0 then b ^-N >0 hence b ^-N * (-infinity) = -infinity

If b=0 then b ^-N =0 and 0 * (-infinity) = undefined

If b<0 and N is even then b ^-N >0 hence b ^-N * (-infinity) = -infinity
but
If b<0 and N is odd then b ^-N <0 hence b ^-N * (-infinity) = +infinity
my conclusion
b ^-N * (-infinity) = -infinity Where N is a natural number and b>0
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Now if it was b ^-N ^ (-infinity) then the answer would be +infinity Where N is a natural number and b>0
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