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Theorem binomlem6 7085
Description: Lemma for binom 7086 (binomial theorem). Do the final induction.
Hypotheses
Ref Expression
binomlem.1 |- A e. CC
binomlem.2 |- B e. CC
Assertion
Ref Expression
binomlem6 |- (N e. NN -> ((A + B)^N) = sum_k e. (0...N)((N C. k) x. ((A^(N - k)) x. (B^k))))
Distinct variable groups:   A,k   B,k   k,N

Proof of Theorem binomlem6
StepHypRef Expression
1 opreq2 3983 . . 3 |- (x = 1 -> ((A + B)^x) = ((A + B)^1))
2 opreq2 3983 . . . 4 |- (x = 1 -> (0...x) = (0...1))
3 opreq1 3982 . . . . . 6 |- (x = 1 -> (x C. k) = (1 C. k))
4 opreq1 3982 . . . . . . . 8 |- (x = 1 -> (x - k) = (1 - k))
54opreq2d 3990 . . . . . . 7 |- (x = 1 -> (A^(x - k)) = (A^(1 - k)))
65opreq1d 3989 . . . . . 6 |- (x = 1 -> ((A^(x - k)) x. (B^k)) = ((A^(1 - k)) x. (B^k)))
73, 6opreq12d 3992 . . . . 5 |- (x = 1 -> ((x C. k) x. ((A^(x - k)) x. (B^k))) = ((1 C. k) x. ((A^(1 - k)) x. (B^k))))
87adantr 391 . . . 4 |- ((x = 1 /\ k e. (0...1)) -> ((x C. k) x. ((A^(x - k)) x. (B^k))) = ((1 C. k) x. ((A^(1 - k)) x. (B^k))))
92, 8sumeq12rdv 7010 . . 3 |- (x = 1 -> sum_k e. (0...x)((x C. k) x. ((A^(x - k)) x. (B^k))) = sum_k e. (0...1)((1 C. k) x. ((A^(1 - k)) x. (B^k))))
101, 9eqeq12d 1496 . 2 |- (x = 1 -> (((A + B)^x) = sum_k e. (0...x)((x C. k) x. ((A^(x - k)) x. (B^k))) <-> ((A + B)^1) = sum_k e. (0...1)((1 C. k) x. ((A^(1 - k)) x. (B^k)))))
11 opreq2 3983 . . 3 |- (x = j -> ((A + B)^x) = ((A + B)^j))
12 opreq2 3983 . . . 4 |- (x = j -> (0...x) = (0...j))
13 opreq1 3982 . . . . . 6 |- (x = j -> (x C. k) = (j C. k))
14 opreq1 3982 . . . . . . . 8 |- (x = j -> (x - k) = (j - k))
1514opreq2d 3990 . . . . . . 7 |- (x = j -> (A^(x - k)) = (A^(j - k)))
1615opreq1d 3989 . . . . . 6 |- (x = j -> ((A^(x - k)) x. (B^k)) = ((A^(j - k)) x. (B^k)))
1713, 16opreq12d 3992 . . . . 5 |- (x = j -> ((x C. k) x. ((A^(x - k)) x. (B^k))) = ((j C. k) x. ((A^(j - k)) x. (B^k))))
1817adantr 391 . . . 4 |- ((x = j /\ k e. (0...j)) -> ((x C. k) x. ((A^(x - k)) x. (B^k))) = ((j C. k) x. ((A^(j - k)) x. (B^k))))
1912, 18sumeq12rdv 7010 . . 3 |- (x = j -> sum_k e. (0...x)((x C. k) x. ((A^(x - k)) x. (B^k))) = sum_k e. (0...j)((j C. k) x. ((A^(j - k)) x. (B^k))))
2011, 19eqeq12d 1496 . 2 |- (x = j -> (((A + B)^x) = sum_k e. (0...x)((x C. k) x. ((A^(x - k)) x. (B^k))) <-> ((A + B)^j) = sum_k e. (0...j)((j C. k) x. ((A^(j - k)) x. (B^k)))))
21 opreq2 3983 . . 3 |- (x = (j + 1) -> ((A + B)^x) = ((A + B)^(j + 1)))
22 opreq2 3983 . . . 4 |- (x = (j + 1) -> (0...x) = (0...(j + 1)))
23 opreq1 3982 . . . . . 6 |- (x = (j + 1) -> (x C. k) = ((j + 1) C. k))
24 opreq1 3982 . . . . . . . 8 |- (x = (j + 1) -> (x - k) = ((j + 1) - k))
2524opreq2d 3990 . . . . . . 7 |- (x = (j + 1) -> (A^(x - k)) = (A^((j + 1) - k)))
2625opreq1d 3989 . . . . . 6 |- (x = (j + 1) -> ((A^(x - k)) x. (B^k)) = ((A^((j + 1) - k)) x. (B^k)))
2723, 26opreq12d 3992 . . . . 5 |- (x = (j + 1) -> ((x C. k) x. ((A^(x - k)) x. (B^k))) = (((j + 1) C. k) x. ((A^((j + 1) - k)) x. (B^k))))
2827adantr 391 . . . 4 |- ((x = (j + 1) /\ k e. (0...(j + 1))) -> ((x C. k) x. ((A^(x - k)) x. (B^k))) = (((j + 1) C. k) x. ((A^((j + 1) - k)) x. (B^k))))
2922, 28sumeq12rdv 7010 . . 3 |- (x = (j + 1) -> sum_k e. (0...x)((x C. k) x. ((A^(x - k)) x. (B^k))) = sum_k e. (0...(j + 1))(((j + 1) C. k) x. ((A^((j + 1) - k)) x. (B^k))))
3021, 29eqeq12d 1496 . 2 |- (x = (j + 1) -> (((A + B)^x) = sum_k e. (0...x)((x C. k) x. ((A^(x - k)) x. (B^k))) <-> ((A + B)^(j + 1)) = sum_k e. (0...(j + 1))(((j + 1) C. k) x. ((A^((j + 1) - k)) x. (B^k)))))
31 opreq2 3983 . . 3 |- (x = N -> ((A + B)^x) = ((A + B)^N))
32 opreq2 3983 . . . 4 |- (x = N -> (0...x) = (0...N))
33 opreq1 3982 . . . . . 6 |- (x = N -> (x C. k) = (N C. k))
34 opreq1 3982 . . . . . . . 8 |- (x = N -> (x - k) = (N - k))
3534opreq2d 3990 . . . . . . 7 |- (x = N -> (A^(x - k)) = (A^(N - k)))
3635opreq1d 3989 . . . . . 6 |- (x = N -> ((A^(x - k)) x. (B^k)) = ((A^(N - k)) x. (B^k)))
3733, 36opreq12d 3992 . . . . 5 |- (x = N -> ((x C. k) x. ((A^(x - k)) x. (B^k))) = ((N C. k) x. ((A^(N - k)) x. (B^k))))
3837adantr 391 . . . 4 |- ((x = N /\ k e. (0...N)) -> ((x C. k) x. ((A^(x - k)) x. (B^k))) = ((N C. k) x. ((A^(N - k)) x. (B^k))))
3932, 38sumeq12rdv 7010 . . 3 |- (x = N -> sum_k e. (0...x)((x C. k) x. ((A^(x - k)) x. (B^k))) = sum_k e. (0...N)((N C. k) x. ((A^(N - k)) x. (B^k))))
4031, 39eqeq12d 1496 . 2 |- (x = N -> (((A + B)^x) = sum_k e. (0...x)((x C. k) x. ((A^(x - k)) x. (B^k))) <-> ((A + B)^N) = sum_k e. (0...N)((N C. k) x. ((A^(N - k)) x. (B^k)))))
41 binomlem.1 . . . . 5 |- A e. CC
42 binomlem.2 . . . . 5 |- B e. CC
4341, 42addcl 5333 . . . 4 |- (A + B) e. CC
44 exp1t 6586 . . . 4 |- ((A + B) e. CC -> ((A + B)^1) = (A + B))
4543, 44ax-mp 7 . . 3 |- ((A + B)^1) = (A + B)
46 0z 6152 . . . . . 6 |- 0 e. ZZ
47 uzidt 6377 . . . . . 6 |- (0 e. ZZ -> 0 e. (ZZ>`
0))
4846, 47ax-mp 7 . . . . 5 |- 0 e. (ZZ>` 0)
49 oprex 3997 . . . . . 6 |- ((1 C. k) x. ((A^(1 - k)) x. (B^k))) e. V
5042elisseti 1825 . . . . . 6 |- B e. V
51 ax1cn 5282 . . . . . . . . 9 |- 1 e. CC
5251addid2 5344 . . . . . . . 8 |- (0 + 1) = 1
5352eqeq2i 1492 . . . . . . 7 |-