15b^2a^5, 5b^5a^3, 21b^5a^6

Question

Find the LCM

Answer 1

first, the numbers

lcm of 15, 5, and 21

15 = 3 * 5

5 = 5

21 = 3 * 7

lcm is 3 * 5 * 7 because 3 * 5 * 7 has 3 * 5 (to make 15), a 5 (to make 5), and 3 * 7 (to make 21)

3 * 5 * 7 = 105

lcm of 15, 5, and 21 is 105

now the b's

the lcm of b^2, b^5, and b^5 is b^5

note b^5 = b^2 * b^3

now the a's

the lcm of a^5, a^3, and a^6 is a^6

the lcm of the whole thing is 105(b^5)(a^6)