Metamath Proof Explorer


Theorem dvnadd

Description: The N -th derivative of the M -th derivative of F is the same as the M + N -th derivative of F . (Contributed by Mario Carneiro, 11-Feb-2015)

Ref Expression
Assertion dvnadd SF𝑝𝑚SM0N0SDnSDnFMN=SDnFM+N

Proof

Step Hyp Ref Expression
1 fveq2 n=0SDnSDnFMn=SDnSDnFM0
2 oveq2 n=0M+n=M+0
3 2 fveq2d n=0SDnFM+n=SDnFM+0
4 1 3 eqeq12d n=0SDnSDnFMn=SDnFM+nSDnSDnFM0=SDnFM+0
5 4 imbi2d n=0SF𝑝𝑚SM0SDnSDnFMn=SDnFM+nSF𝑝𝑚SM0SDnSDnFM0=SDnFM+0
6 fveq2 n=kSDnSDnFMn=SDnSDnFMk
7 oveq2 n=kM+n=M+k
8 7 fveq2d n=kSDnFM+n=SDnFM+k
9 6 8 eqeq12d n=kSDnSDnFMn=SDnFM+nSDnSDnFMk=SDnFM+k
10 9 imbi2d n=kSF𝑝𝑚SM0SDnSDnFMn=SDnFM+nSF𝑝𝑚SM0SDnSDnFMk=SDnFM+k
11 fveq2 n=k+1SDnSDnFMn=SDnSDnFMk+1
12 oveq2 n=k+1M+n=M+k+1
13 12 fveq2d n=k+1SDnFM+n=SDnFM+k+1
14 11 13 eqeq12d n=k+1SDnSDnFMn=SDnFM+nSDnSDnFMk+1=SDnFM+k+1
15 14 imbi2d n=k+1SF𝑝𝑚SM0SDnSDnFMn=SDnFM+nSF𝑝𝑚SM0SDnSDnFMk+1=SDnFM+k+1
16 fveq2 n=NSDnSDnFMn=SDnSDnFMN
17 oveq2 n=NM+n=M+N
18 17 fveq2d n=NSDnFM+n=SDnFM+N
19 16 18 eqeq12d n=NSDnSDnFMn=SDnFM+nSDnSDnFMN=SDnFM+N
20 19 imbi2d n=NSF𝑝𝑚SM0SDnSDnFMn=SDnFM+nSF𝑝𝑚SM0SDnSDnFMN=SDnFM+N
21 recnprss SS
22 21 ad2antrr SF𝑝𝑚SM0S
23 ssidd SF𝑝𝑚S
24 cnex V
25 elpm2g VSF𝑝𝑚SF:domFdomFS
26 24 25 mpan SF𝑝𝑚SF:domFdomFS
27 26 simplbda SF𝑝𝑚SdomFS
28 24 a1i SF𝑝𝑚SV
29 simpl SF𝑝𝑚SS
30 pmss12g domFSVS𝑝𝑚domF𝑝𝑚S
31 23 27 28 29 30 syl22anc SF𝑝𝑚S𝑝𝑚domF𝑝𝑚S
32 31 adantr SF𝑝𝑚SM0𝑝𝑚domF𝑝𝑚S
33 dvnff SF𝑝𝑚SSDnF:0𝑝𝑚domF
34 33 ffvelcdmda SF𝑝𝑚SM0SDnFM𝑝𝑚domF
35 32 34 sseldd SF𝑝𝑚SM0SDnFM𝑝𝑚S
36 dvn0 SSDnFM𝑝𝑚SSDnSDnFM0=SDnFM
37 22 35 36 syl2anc SF𝑝𝑚SM0SDnSDnFM0=SDnFM
38 nn0cn M0M
39 38 adantl SF𝑝𝑚SM0M
40 39 addridd SF𝑝𝑚SM0M+0=M
41 40 fveq2d SF𝑝𝑚SM0SDnFM+0=SDnFM
42 37 41 eqtr4d SF𝑝𝑚SM0SDnSDnFM0=SDnFM+0
43 oveq2 SDnSDnFMk=SDnFM+kSDSDnSDnFMk=SDSDnFM+k
44 22 adantr SF𝑝𝑚SM0k0S
45 35 adantr SF𝑝𝑚SM0k0SDnFM𝑝𝑚S
46 simpr SF𝑝𝑚SM0k0k0
47 dvnp1 SSDnFM𝑝𝑚Sk0SDnSDnFMk+1=SDSDnSDnFMk
48 44 45 46 47 syl3anc SF𝑝𝑚SM0k0SDnSDnFMk+1=SDSDnSDnFMk
49 39 adantr SF𝑝𝑚SM0k0M
50 nn0cn k0k
51 50 adantl SF𝑝𝑚SM0k0k
52 1cnd SF𝑝𝑚SM0k01
53 49 51 52 addassd SF𝑝𝑚SM0k0M+k+1=M+k+1
54 53 fveq2d SF𝑝𝑚SM0k0SDnFM+k+1=SDnFM+k+1
55 simpllr SF𝑝𝑚SM0k0F𝑝𝑚S
56 nn0addcl M0k0M+k0
57 56 adantll SF𝑝𝑚SM0k0M+k0
58 dvnp1 SF𝑝𝑚SM+k0SDnFM+k+1=SDSDnFM+k
59 44 55 57 58 syl3anc SF𝑝𝑚SM0k0SDnFM+k+1=SDSDnFM+k
60 54 59 eqtr3d SF𝑝𝑚SM0k0SDnFM+k+1=SDSDnFM+k
61 48 60 eqeq12d SF𝑝𝑚SM0k0SDnSDnFMk+1=SDnFM+k+1SDSDnSDnFMk=SDSDnFM+k
62 43 61 imbitrrid SF𝑝𝑚SM0k0SDnSDnFMk=SDnFM+kSDnSDnFMk+1=SDnFM+k+1
63 62 expcom k0SF𝑝𝑚SM0SDnSDnFMk=SDnFM+kSDnSDnFMk+1=SDnFM+k+1
64 63 a2d k0SF𝑝𝑚SM0SDnSDnFMk=SDnFM+kSF𝑝𝑚SM0SDnSDnFMk+1=SDnFM+k+1
65 5 10 15 20 42 64 nn0ind N0SF𝑝𝑚SM0SDnSDnFMN=SDnFM+N
66 65 com12 SF𝑝𝑚SM0N0SDnSDnFMN=SDnFM+N
67 66 impr SF𝑝𝑚SM0N0SDnSDnFMN=SDnFM+N