Question

Using factor theorem show that + 5x + 6 is a factor of : x + 5x + 9x + 15x + 18​

Answer 1

Using factor theorem: we know that if ax+b is factor of any polynomial p(x) then then p(-b/a) = 0

So here: ax+b = 5x+6 and p(x)= x+5x+9x+15x+18 = 30x+18 so

P(-6/5)= 30(-6/5) + 18 = -36+18 = -18 wich is not 0 so p( x) is not a factor of 5x+6