What's wrong with this demonstration? (1 = -1)
3712
Why $\sqrt{-1 \cdot {-1}} \neq \sqrt{-1}^2$?
6650
Why $\sqrt{-1 \times -1} \neq \sqrt{-1}^2$?
116043
Why is a raised to the power of Zero is 1?
96554
Why is $x^0 = 1$ except when $x = 0$?
111938
How do I find a flaw in this false proof that $7n = 0$ for all natural numbers?
51877
Why is this 'Proof' by induction not valid?
97952
Square root of 1 is (not) -1
147528
Where's the error in this $2=1$ fake proof?
142401
Where's the problem in this equation? Resulting in $4 = 5$
80004
Why is $1/i$ equal to $-i$?
17211
Is it wrong to tell children that $1/0 =$ NaN is incorrect, and should be $∞$?
53123
Trying to derive a contradiction with this simple inequality,
158842
What is wrong with this bijection from all naturals to reals between 0 and 1?
14633
What's the thing with $\sqrt{-1} = i$
101169
Prove that $x^2 = - 1$ has no solution in $\mathbb{Z}$
55487
Can someone help what is incorrect in this program?
130854
Constructing example showing $\mathbb{E}(X^{-1})=(\mathbb{E}(X))^{-1}$