The multiplication sign * might be familiar as the multiplication for programmer, but I'm not sure about ordinary user. I don't know if I should use * or x for multiplication.

Someone recently asked me why a negative $\\times$ a negative is positive, and why a negative $\\times$ a positive is negative, etc. I went ahead and gave them a proof by contradiction like …

Jun 30, 2016 · Why does the " × × " used in arithmetic change to a " ⋅ " as we progress through education? The symbol seems to only be ambiguous because of the variable x x; however, we …

23 We all learned in our early years that when dividing both sides by a negative number, we reverse the inequality sign. Take −3x <9 3 x <9 To solve for x x, we divide both sides by −3 3 …

Jan 29, 2018 · Closed 7 years ago. What is the difference between 2*a and 2a? What is the difference between 2 (3+4) and 2* (3+4)? We all know that omitting the multiplication sign still …

Aug 23, 2016 · What is the difference between the symbols for multiplication, dot product, and cross product symbols? How can we tell them apart?

Dec 24, 2025 · A simple example where it does not work is a $2 \times 2$ grid if you assign $+1$ to all left and bottom boundary values.

Dec 19, 2025 · I have a partial result, which may possibly be adapted to a full proof of non-existence. Firstly, I show that no such function exists for the $1$ -dimensional analogue. …

Jul 19, 2020 · Assume for convenience that g g changes sign on [0, a] [0, a] only a finite number p p of times (the infinite case is actually easier as we will see in the proof).

Feb 8, 2014 · My thinking is that negative 1 is negative 1 times 1. So in conclusion, I pulled that negative zero (can be expressed by "-a") is negative 1 times 0, or just 0 (-a = -1 * a).