READING: II §2 O7
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II §2 O6
begin quote ita"
CHAPTER II [:] The Real Number System [...] §2. ORDER. "end quote
Please get the book and read along. topic index contents
O7: THE MULTIPLICATIVE INVERSES OF THE POSITIVE REAL NUMBERS ARE GREATER THAN ZERO
Please recall that the division b/a is defined to be b·a.
Consequently, if b=1 we have 1/a = 1·a = a.
If a0, then 1/a0. In fact a·(1/a)=10, which would contradict the rules of sign [O5] if we had 1/a0.
on to O8