Metamath Proof Explorer


Theorem fourierdlem8

Description: A partition interval is a subset of the partitioned interval. (Contributed by Glauco Siliprandi, 11-Dec-2019)

Ref Expression
Hypotheses fourierdlem8.a φA*
fourierdlem8.b φB*
fourierdlem8.q φQ:0MAB
fourierdlem8.i φI0..^M
Assertion fourierdlem8 φQIQI+1AB

Proof

Step Hyp Ref Expression
1 fourierdlem8.a φA*
2 fourierdlem8.b φB*
3 fourierdlem8.q φQ:0MAB
4 fourierdlem8.i φI0..^M
5 1 adantr φxQIQI+1A*
6 2 adantr φxQIQI+1B*
7 3 adantr φxQIQI+1Q:0MAB
8 4 adantr φxQIQI+1I0..^M
9 simpr φxQIQI+1xQIQI+1
10 5 6 7 8 9 fourierdlem1 φxQIQI+1xAB
11 10 ralrimiva φxQIQI+1xAB
12 dfss3 QIQI+1ABxQIQI+1xAB
13 11 12 sylibr φQIQI+1AB