No you can't, but sometimes you can.
You can always find a common multiple of two numbers by multiplying them together; it will not always be the least common multiple. As one counterexample, if one of the numbers is a multiple of the other, the first number is the LCM of the two. 9 x 3 = 27 The LCM of 9 and 3 is 9. 4 x 6 = 24 The LCM of 4 and 6 is 12.
No, that will not always work. in the case for some numbers it will work. for example 3 * 4 = 12. it works here. however if you do that for 30 and 20, you will get 600. the real lowest common multiple is 60. so it does not always work.
This does not work when one of the numbers is negative.
Only if they are odd.
There is always going to be a LCM. Just multiply the two numbers together to get the a common multiple if you cant find one because the two numbers multiplied together is a common multiple.
For any non-zero whole numbers, there are ALWAYS multiples that are the same. That's the whole point in finding the least common multiple! For example, simply by multiplying the two numbers, you get a common multiple. However, there is no guarantee that it will be the LEAST common multiple. On the other hand, writing down lots of multiples and looking for common multiples is not very efficient, except perhaps for very low numbers. A better method is to factor each of the numbers into prime factors, then use any prime factor that appears in one or more of the numbers for your result. Use the highest power. For example, if one number has a factor of 2 to the power 3, and the other has 2 to the power 2, use 2 to the power 3. Multiplying all those prime factors together gives you the least common multiple.
The product of two numbers is the two numbers multiplied together. When multiplying a positive number and a negative number, the answer is always negative. For example: 7*-3= -21
Common multiples include any multiple of 4655.
No, this will find a common multiple, but not always the least. For example, 2 and 4 have a least common multiple of 4 but if you multiply them you get 8. In fact, the LCM will only be the product of two numbers if the numbers have no common factors. We call numbers with no common factors relatively prime.
For any two positive integers x and y, an LCM exists. If it exists, we can identify it.
Yes, two natural numbers always have a least common multiple.
28, 56, 84 you can always find a common multiple of two numbers by multiplying them (but that won't always be the least common multiple)... the other common multiples can b found by multiplying that number with any other positive integer... for example, if you have two numbers (a and b), then one of their common multiples is a x b (but not always the smallest one), and the others are 2 x a x b, or any other positive integer times a x b