algebra
posted by lisa .
1. Find the LCM of (8+7), (6449v^2), and (87v)
2. Find the LCM of 14x^7 and 98x^5
3. Find all numbers for which the rational expression is undefined
5/v9

I'll assume that 8+7 is really 8+7v
Note that 6449v^2 = (8+7v)(87v), so that would also be the LCM of those three expressions.
14x^7 = 14x^5 * x^2
98x^5 = 14x^5 * 7
LCM(a,b) = ab/GCD(a,b)
GCD = 14x^5
LCM = 14x^7 * 98x^5 / 14x^5 = 98x^7