I'm having some troubles with exercise 10.5.3 a) from Bondy and Murty, Graph Theory, 2008, pp-273
a) Let F be a graph with maximum degree at most 3. Show that a graph has an F-minor if and only if it contains an F-subdivision.
I already have the converse, I took the subdivision and by the allowed operations I got an F-minor, but I never used the degree sentence. I'm stucked on proving the direct implication, I don't see how to use the degree sentence again. My idea is starting with the minor and doing exactly the converse operation in the reverse order for the sequence operation done in G to obtain the minor and that should be a graph containing a subdivision of F because the operations that really matters are vertice splitting but again I can't see how the degree sequence is fundamental here.
Can someone please help me? Thanks in advance