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Theorem projlem7 5199
Description: Part of Lemma 3.6 of [Beran] p. 101. Applies weak deduction theorem to projlem6 5198. Used by projlem19 5211.
Hypotheses
Ref Expression
projlem5.1 |- A e. H~
projlem5.2 |- B e. H~
projlem5.3 |- C e. H~
projlem5.4 |- R e. RR
projlem5.5 |- 0 <_ R
projlem5.6 |- (4 x. (R^2)) <_ ((norm`
((B +v C) -v (2 .s A)))^2)
projlem5.7 |- D e. NN
projlem5.8 |- G e. NN
projlem5.9 |- N e. NN
Assertion
Ref Expression
projlem7 |- (((norm` (B -v A)) < (R + (1 / D)) /\ (norm` (C -v A)) < (R + (1 / G))) -> ((N <_ D /\ N <_ G) -> (norm` (B -v C)) < (sqr`
((4 x. ((2 x. R) + 1)) / N))))

Proof of Theorem projlem7
StepHypRef Expression
1 opreq1 3006 . . . . 5 |- (B = if(((norm` (B -v A)) < (R + (1 / D)) /\ (norm` (C -v A)) < (R + (1 / G))), B, A) -> (B -v C) = (if(((norm` (B -v A)) < (R + (1 / D)) /\ (norm` (C -v A)) < (R + (1 / G))), B, A) -v C))
21fveq2d 2836 . . . 4 |- (B = if(((norm` (B -v A)) < (R + (1 / D)) /\ (norm` (C -v A)) < (R + (1 / G))), B, A) -> (norm` (B -v C)) = (norm` (if(((norm` (B -v A)) < (R + (1 / D)) /\ (norm` (C -v A)) < (R + (1 / G))), B, A) -v C)))
32breq1d 2071 . . 3 |- (B = if(((norm` (B -v A)) < (R + (1 / D)) /\ (norm` (C -v A)) < (R + (1 / G))), B, A) -> ((norm` (B -v C)) < (sqr`
((4 x. ((2 x. R) + 1)) / N)) <-> (norm` (if(((norm`
(B -v A)) < (R + (1 / D)) /\ (norm`
(C -v A)) < (R + (1 / G))), B, A) -v C)) < (sqr` ((4 x. ((2 x. R) + 1)) / N))))
43imbi2d 464 . 2 |- (B = if(((norm` (B -v A)) < (R + (1 / D)) /\ (norm` (C -v A)) < (R + (1 / G))), B, A) -> (((N <_ D /\ N <_ G) -> (norm` (B -v C)) < (sqr` ((4 x. ((2 x. R) + 1)) / N))) <-> ((N <_ D /\ N <_ G) -> (norm` (if(((norm` (B -v A)) < (R + (1 / D)) /\ (norm` (C -v A)) < (R + (1 / G))), B, A) -v C)) < (sqr` ((4 x. ((2 x. R) + 1)) / N)))))
5 opreq2 3007 . . . . 5 |- (C = if(((norm` (B -v A)) < (R + (1 / D)) /\ (norm` (C -v A)) < (R + (1 / G))), C, A) -> (if(((norm` (B -v A)) < (R + (1 / D)) /\ (norm` (C -v A)) < (R + (1 / G))), B, A) -v C) = (if(((norm` (B -v A)) < (R + (1 / D)) /\ (norm` (C -v A)) < (R + (1 / G))), B, A) -v if(((norm` (B -v A)) < (R + (1 / D)) /\ (norm` (C -v A)) < (R + (1 / G))), C, A)))
65fveq2d 2836 . . . 4 |- (C = if(((norm` (B -v A)) < (R + (1 / D)) /\ (norm` (C -v A)) < (R + (1 / G))), C, A) -> (norm` (if(((norm` (B -v A)) < (R + (1 / D)) /\ (norm` (C -v A)) < (R + (1 / G))), B, A) -v C)) = (norm` (if(((norm`
(B -v A)) < (R + (1 / D)) /\ (norm`
(C -v A)) < (R + (1 / G))), B, A) -v if(((norm` (B -v A)) < (R + (1 / D)) /\ (norm` (C -v A)) < (R + (1 / G))), C, A))))
76breq1d 2071 . . 3 |- (C = if(((norm` (B -v A)) < (R + (1 / D)) /\ (norm` (C -v A)) < (R + (1 / G))), C, A) -> ((norm` (if(((norm` (B -v A)) < (R + (1 / D)) /\ (norm` (C -v A)) < (R + (1 / G))), B, A) -v C)) < (sqr` ((4 x. ((2 x. R) + 1)) / N)) <-> (norm` (if(((norm` (B -v A)) < (R + (1 / D)) /\ (norm` (C -v A)) < (R + (1 / G))), B, A) -v if(((norm` (B -v A)) < (R + (1 / D)) /\ (norm` (C -v A)) < (R + (1 / G))), C, A))) < (sqr` ((4 x. ((2 x. R) + 1)) / N))))
87imbi2d 464 . 2 |- (C = if(((norm` (B -v A)) < (R + (1 / D)) /\ (norm` (C -v A)) < (R + (1 / G))), C, A) -> (((N <_ D /\ N <_ G) -> (norm` (if(((norm` (B -v A)) < (R + (1 / D)) /\ (norm` (C -v A)) < (R + (1 / G))), B, A) -v C)) < (sqr` ((4 x. ((2 x. R) + 1)) / N))) <-> ((N <_ D /\ N <_ G) -> (norm` (if(((norm` (B -v A)) < (R + (1 / D)) /\ (norm` (C -v A)) < (R + (1 / G))), B, A) -v if(((norm`
(B -v A)) < (R + (1 / D)) /\ (norm`
(C -v A)) < (R + (1 / G))), C, A))) < (sqr`
((4 x. ((2 x. R) + 1)) / N)))))
9 opreq2 3007 . . . . . . . 8 |- (R = if(((norm` (B -v A)) < (R + (1 / D)) /\ (norm` (C -v A)) < (R + (1 / G))), R, 0) -> (2 x. R) = (2 x. if(((norm` (B -v A)) < (R + (1 / D)) /\ (norm` (C -v A)) < (R + (1 / G))), R, 0)))
109opreq1d 3012 . . . . . . 7 |- (R = if(((norm` (B -v A)) < (R + (1 / D)) /\ (norm` (C -v A)) < (R + (1 / G))), R, 0) -> ((2 x. R) + 1) = ((2 x. if(((norm` (B -v A)) < (R + (1 / D)) /\ (norm` (C -v A)) < (R + (1 / G))), R, 0)) + 1))
1110opreq2d 3013 . . . . . 6 |- (R = if(((norm` (B -v A)) < (R + (1 / D)) /\ (norm` (C -v A)) < (R + (1 / G))), R, 0) -> (4 x. ((2 x. R) + 1)) = (4 x. ((2 x. if(((norm` (B -v A)) < (R + (1 / D)) /\ (norm` (C -v A)) < (R + (1 / G))), R, 0)) + 1)))
1211opreq1d 3012 . . . . 5 |- (R = if(((norm` (B -v A)) < (R + (1 / D)) /\ (norm` (C -v A)) < (R + (1 / G))), R, 0) -> ((4 x. ((2 x. R) + 1)) / N) = ((4 x. ((2 x. if(((norm` (B -v A)) < (R + (1 / D)) /\ (norm` (C -v A)) < (R + (1 / G))), R, 0)) + 1)) / N))
1312fveq2d 2836 . . . 4 |- (R = if(((norm` (B -v A)) < (R + (1 / D)) /\ (norm