Is the least common multiple of an even $2k$ and odd number $2l+1$ always the product of both numbers $2k(2l+1)$ ?
And also is the least common multiples of two odd numbers the product of both odd numbers?
Thank you.
Is the least common multiple of an even $2k$ and odd number $2l+1$ always the product of both numbers $2k(2l+1)$ ?
And also is the least common multiples of two odd numbers the product of both odd numbers?
Thank you.
On
No, the least common multiple is the least number which is divisible by both the numbers. Counter Examples
$$1)LCM(6,9)=18\neq 54 = 6\times 9$$ $$2)LCM(3,9)=9\neq 27 = 3\times 9$$
Hope it is helpful:)
On
If we take 6 and 15 then their lcm is 30 so your first question has answer "no"
If we take 3 and 15 then their lcm is 15 so your second question has answer "no"
On
No. The only times either works, is if gcd(x,y)=1 . Otherwise, it fails 15 and 3 for example have gcd of 3. that mean's if we multiply them to get their product, we have a number with a factor of 9 which neither number has on it's own. We have to only have factors the original numbers have.
This works in general, lcm(4,4)=4 not 16, lcm(6,3)=6 not 18, lcm(8,12)=24 not 96, etc.
For two numbers $a,b$ we have $$lcm(a,b)=\frac{ab}{\gcd(a,b)}$$ so even if $a$ is odd and $b$ is even , the result need not be $ab$. The same situation when both numbers are odd.