Answer:
x3
Step-by-step explanation:
Considering x4 and x3 actually power terms.
I mean: x4 is [tex]x^{4}[/tex] and x3 is [tex]x^{3}[/tex].
Let's decompose the first term: [tex]x^{4}=x^{3}.x[/tex]
Now it is clear that the common factor is [tex]x^{3}[/tex].
