how can I prove negative times negative is positive.
17515
Why is negative times negative = positive?
45323
How to prove $\vdash\neg P\to (P\to Q)$?
55094
How to show $i^{-1} = -i$?
104148
Showing the norm' is non-negative
141496
Could someone make the proof into a hinted exercise?
113506
negative number divided by positive number, what would be remainder?
157733
Are positive real numbers $x,y$ allowed to be taken out during this proof?
115506
What's wrong with this demonstration? (1 = -1)
68233
Fermat's little theorem's proof for a negative integer
110271
Given a matrix with non-negative real entries, can you algebraically prove that it has a non-negative eigenvalue?
120676
A certain element which makes functionals positive
86866
Is there a number whose absolute value is negative?
20863
how do I prove this inequallity?
127211
How does Java calculate negative numbers?
118036
Proving at least 99 pairwise sums of the reals are non-negative
130722
Can you prove this property?
83713
If $z,w\in \mathbb{C}^{\times}$, then $|z+w|=|z|+|w|$ iff $w=tz$ for some $t\gt 0$