It doesn’t prove U()=100, it proves [A()=1 implies U()=100]. Simultaneously having the proof that [A()=1 implies U()=5] allows you to disprove A()=1, which is perfectly fine, since actually A()=2.
It doesn’t prove U()=100, it proves [A()=1 implies U()=100]. Simultaneously having the proof that [A()=1 implies U()=5] allows you to disprove A()=1, which is perfectly fine, since actually A()=2.