How do you find all the zeros of x28x48=0 with its multiplicities?

1 Answer
Apr 16, 2016

x=12 or x=4, each with multiplicity 1

Explanation:

Complete the square then use the difference of squares identity:

a2b2=(ab)(a+b)

with a=(x4) and b=8 as follows:

0=x28x48

=(x4)21648

=(x4)282

=((x4)8)((x4)+8)

=(x12)(x+4)

So x=12 or x=4, each with multiplicity 1