Sometimes true. (when the numbers are mutually prime)
e.g. it's true for 5 and 7, 8 and 3.
But it's not true when they have a factor in common e.g. 6 and 8, or 15 and 20.
Sometimes true.
The LCM of two numbers is sometimes the product of the two numbers.
Not always. The product of two numbers will always be a common multiple, but it will not always be least. The product of 4 and 9 is 36. The LCM of 4 and 9 is 36. The product of 4 and 8 is 32. The LCM of 4 and 8 is 16.
The product of all those numbers will always be a negative number.
Yes, it is.
Sometimes true. The LCM of 4 and 9 is 36. The LCM of 4 and 8 is 8.
Sometimes, not always.
Sometimes true.
The LCM of two numbers is sometimes the product of the two numbers.
Sometimes.
Sometimes, not always.
No, it is always true
No, it is always true.
Sometimes, not always. The LCM of 5 and 7 is 35. The LCM of 5 and 10 is 10.
Yes, the least common multiple is the product of the two numbers or the lowest number that both multiples can go into.
If by "opposite" you mean "additive inverse", then yes.
The product of negative number and a positive number is always a negative. The product of two positive numbers, or two negative numbers, is always a positive.