Why $\sqrt{-1 \times -1} \neq \sqrt{-1}^2$?
3712
Why $\sqrt{-1 \cdot {-1}} \neq \sqrt{-1}^2$?
80004
Why is $1/i$ equal to $-i$?
102138
Why does $\sqrt{x^2}$ seem to equal $x$ and not $|x|$ when you multiply the exponents?
54030
Square and square root and negative numbers
154001
$(g\circ f)^{-1}=f^{-1}\circ g^{-1}$
110826
prove that : $ i = \sqrt {-1}\ $
103223
If $x^a$ is $x$ multiplied $a$ times, then how does $x^{-1}$ make sense?
16931
Can one do the maths of physics without using $\sqrt{-1}$?
12217
What is so special about $\alpha=-1$ in the integral of $x^\alpha$?
146180
Prove that $x\sqrt{1-x^2} \leq \sin x \leq x$
87848
Formal proof for $(-1) \times (-1) = 1$
107390
Why is (-1)(-1) = 1?
151930
What does it mean by $t=-1$?
95057
Possible fake proof of $1= -1$
66082
Using $\sqrt{1-t}\leq 1-\frac t2$ to show that $\frac{1\cdot3\cdot5\cdots(2n-1)}{2\cdot4\cdot6\cdots2n}\geq\frac1{2\sqrt n}$
98921
Does $y(y+1) \leq (x+1)^2$ imply $y(y-1) \leq x^2$?
68746
What is $f(f^{-1}(A))$?