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Theorem xnegdi 12078
Description: Extended real version of xnegdi 12078. (Contributed by Mario Carneiro, 20-Aug-2015.)
Assertion
Ref Expression
xnegdi  |-  ( ( A  e.  RR*  /\  B  e.  RR* )  ->  -e
( A +e
B )  =  ( 
-e A +e  -e B ) )

Proof of Theorem xnegdi
StepHypRef Expression
1 elxr 11950 . 2  |-  ( A  e.  RR*  <->  ( A  e.  RR  \/  A  = +oo  \/  A  = -oo ) )
2 elxr 11950 . . . 4  |-  ( B  e.  RR*  <->  ( B  e.  RR  \/  B  = +oo  \/  B  = -oo ) )
3 recn 10026 . . . . . . . 8  |-  ( A  e.  RR  ->  A  e.  CC )
4 recn 10026 . . . . . . . 8  |-  ( B  e.  RR  ->  B  e.  CC )
5 negdi 10338 . . . . . . . 8  |-  ( ( A  e.  CC  /\  B  e.  CC )  -> 
-u ( A  +  B )  =  (
-u A  +  -u B ) )
63, 4, 5syl2an 494 . . . . . . 7  |-  ( ( A  e.  RR  /\  B  e.  RR )  -> 
-u ( A  +  B )  =  (
-u A  +  -u B ) )
7 readdcl 10019 . . . . . . . 8  |-  ( ( A  e.  RR  /\  B  e.  RR )  ->  ( A  +  B
)  e.  RR )
8 rexneg 12042 . . . . . . . 8  |-  ( ( A  +  B )  e.  RR  ->  -e
( A  +  B
)  =  -u ( A  +  B )
)
97, 8syl 17 . . . . . . 7  |-  ( ( A  e.  RR  /\  B  e.  RR )  -> 
-e ( A  +  B )  = 
-u ( A  +  B ) )
10 renegcl 10344 . . . . . . . 8  |-  ( A  e.  RR  ->  -u A  e.  RR )
11 renegcl 10344 . . . . . . . 8  |-  ( B  e.  RR  ->  -u B  e.  RR )
12 rexadd 12063 . . . . . . . 8  |-  ( (
-u A  e.  RR  /\  -u B  e.  RR )  ->  ( -u A +e -u B
)  =  ( -u A  +  -u B ) )
1310, 11, 12syl2an 494 . . . . . . 7  |-  ( ( A  e.  RR  /\  B  e.  RR )  ->  ( -u A +e -u B )  =  ( -u A  +  -u B ) )
146, 9, 133eqtr4d 2666 . . . . . 6  |-  ( ( A  e.  RR  /\  B  e.  RR )  -> 
-e ( A  +  B )  =  ( -u A +e -u B ) )
15 rexadd 12063 . . . . . . 7  |-  ( ( A  e.  RR  /\  B  e.  RR )  ->  ( A +e
B )  =  ( A  +  B ) )
16 xnegeq 12038 . . . . . . 7  |-  ( ( A +e B )  =  ( A  +  B )  ->  -e ( A +e B )  = 
-e ( A  +  B ) )
1715, 16syl 17 . . . . . 6  |-  ( ( A  e.  RR  /\  B  e.  RR )  -> 
-e ( A +e B )  =  -e ( A  +  B ) )
18 rexneg 12042 . . . . . . 7  |-  ( A  e.  RR  ->  -e
A  =  -u A
)
19 rexneg 12042 . . . . . . 7  |-  ( B  e.  RR  ->  -e
B  =  -u B
)
2018, 19oveqan12d 6669 . . . . . 6  |-  ( ( A  e.  RR  /\  B  e.  RR )  ->  (  -e A +e  -e
B )  =  (
-u A +e -u B ) )
2114, 17, 203eqtr4d 2666 . . . . 5  |-  ( ( A  e.  RR  /\  B  e.  RR )  -> 
-e ( A +e B )  =  (  -e
A +e  -e B ) )
22 xnegpnf 12040 . . . . . 6  |-  -e +oo  = -oo
23 oveq2 6658 . . . . . . . 8  |-  ( B  = +oo  ->  ( A +e B )  =  ( A +e +oo ) )
24 rexr 10085 . . . . . . . . 9  |-  ( A  e.  RR  ->  A  e.  RR* )
25 renemnf 10088 . . . . . . . . 9  |-  ( A  e.  RR  ->  A  =/= -oo )
26 xaddpnf1 12057 . . . . . . . . 9  |-  ( ( A  e.  RR*  /\  A  =/= -oo )  ->  ( A +e +oo )  = +oo )
2724, 25, 26syl2anc 693 . . . . . . . 8  |-  ( A  e.  RR  ->  ( A +e +oo )  = +oo )
2823, 27sylan9eqr 2678 . . . . . . 7  |-  ( ( A  e.  RR  /\  B  = +oo )  ->  ( A +e
B )  = +oo )
29 xnegeq 12038 . . . . . . 7  |-  ( ( A +e B )  = +oo  ->  -e ( A +e B )  = 
-e +oo )
3028, 29syl 17 . . . . . 6  |-  ( ( A  e.  RR  /\  B  = +oo )  -> 
-e ( A +e B )  =  -e +oo )
31 xnegeq 12038 . . . . . . . . 9  |-  ( B  = +oo  ->  -e
B  =  -e +oo )
3231, 22syl6eq 2672 . . . . . . . 8  |-  ( B  = +oo  ->  -e
B  = -oo )
3332oveq2d 6666 . . . . . . 7  |-  ( B  = +oo  ->  (  -e A +e  -e B )  =  (  -e A +e -oo )
)
3418, 10eqeltrd 2701 . . . . . . . 8  |-  ( A  e.  RR  ->  -e
A  e.  RR )
35 rexr 10085 . . . . . . . . 9  |-  (  -e A  e.  RR  -> 
-e A  e. 
RR* )
36 renepnf 10087 . . . . . . . . 9  |-  (  -e A  e.  RR  -> 
-e A  =/= +oo )
37 xaddmnf1 12059 . . . . . . . . 9  |-  ( ( 
-e A  e. 
RR*  /\  -e A  =/= +oo )  -> 
(  -e A +e -oo )  = -oo )
3835, 36, 37syl2anc 693 . . . . . . . 8  |-  (  -e A  e.  RR  ->  (  -e A +e -oo )  = -oo )
3934, 38syl 17 . . . . . . 7  |-  ( A  e.  RR  ->  (  -e A +e -oo )  = -oo )
4033, 39sylan9eqr 2678 . . . . . 6  |-  ( ( A  e.  RR  /\  B  = +oo )  ->  (  -e A +e  -e
B )  = -oo )
4122, 30, 403eqtr4a 2682 . . . . 5  |-  ( ( A  e.  RR  /\  B  = +oo )  -> 
-e ( A +e B )  =  (  -e
A +e  -e B ) )
42 xnegmnf 12041 . . . . . 6  |-  -e -oo  = +oo
43 oveq2 6658 . . . . . . . 8  |-  ( B  = -oo  ->  ( A +e B )  =  ( A +e -oo ) )
44 renepnf 10087 . . . . . . . . 9  |-  ( A  e.  RR  ->  A  =/= +oo )
45 xaddmnf1 12059 . . . . . . . . 9  |-  ( ( A  e.  RR*  /\  A  =/= +oo )  ->  ( A +e -oo )  = -oo )
4624, 44, 45syl2anc 693 . . . . . . . 8  |-  ( A  e.  RR  ->  ( A +e -oo )  = -oo )
4743, 46sylan9eqr 2678 . . . . . . 7  |-  ( ( A  e.  RR  /\  B  = -oo )  ->  ( A +e
B )  = -oo )
48 xnegeq 12038 . . . . . . 7  |-  ( ( A +e B )  = -oo  ->  -e ( A +e B )  = 
-e -oo )
4947, 48syl 17 . . . . . 6  |-  ( ( A  e.  RR  /\  B  = -oo )  -> 
-e ( A +e B )  =  -e -oo )
50 xnegeq 12038 . . . . . . . . 9  |-  ( B  = -oo  ->  -e
B  =  -e -oo )
5150, 42syl6eq 2672 . . . . . . . 8  |-  ( B  = -oo  ->  -e
B  = +oo )
5251oveq2d 6666 . . . . . . 7  |-  ( B  = -oo  ->  (  -e A +e  -e B )  =  (  -e A +e +oo )
)
53 renemnf 10088 . . . . . . . . 9  |-  (  -e A  e.  RR  -> 
-e A  =/= -oo )
54 xaddpnf1 12057 . . . . . . . . 9  |-  ( ( 
-e A  e. 
RR*  /\  -e A  =/= -oo )  -> 
(  -e A +e +oo )  = +oo )
5535, 53, 54syl2anc 693 . . . . . . . 8  |-  (  -e A  e.  RR  ->  (  -e A +e +oo )  = +oo )
5634, 55syl 17 . . . . . . 7  |-  ( A  e.  RR  ->  (  -e A +e +oo )  = +oo )
5752, 56sylan9eqr 2678 . . . . . 6  |-  ( ( A  e.  RR  /\  B  = -oo )  ->  (  -e A +e  -e
B )  = +oo )
5842, 49, 573eqtr4a 2682 . . . . 5  |-  ( ( A  e.  RR  /\  B  = -oo )  -> 
-e ( A +e B )  =  (  -e
A +e  -e B ) )
5921, 41, 583jaodan 1394 . . . 4  |-  ( ( A  e.  RR  /\  ( B  e.  RR  \/  B  = +oo  \/  B  = -oo ) )  ->  -e
( A +e
B )  =  ( 
-e A +e  -e B ) )
602, 59sylan2b 492 . . 3  |-  ( ( A  e.  RR  /\  B  e.  RR* )  ->  -e ( A +e B )  =  (  -e A +e  -e
B ) )
61 xneg0 12043 . . . . . . 7  |-  -e 0  =  0
62 simpr 477 . . . . . . . . . 10  |-  ( ( B  e.  RR*  /\  B  = -oo )  ->  B  = -oo )
6362oveq2d 6666 . . . . . . . . 9  |-  ( ( B  e.  RR*  /\  B  = -oo )  ->  ( +oo +e B )  =  ( +oo +e -oo ) )
64 pnfaddmnf 12061 . . . . . . . . 9  |-  ( +oo +e -oo )  =  0
6563, 64syl6eq 2672 . . . . . . . 8  |-  ( ( B  e.  RR*  /\  B  = -oo )  ->  ( +oo +e B )  =  0 )
66 xnegeq 12038 . . . . . . . 8  |-  ( ( +oo +e B )  =  0  ->  -e ( +oo +e B )  = 
-e 0 )
6765, 66syl 17 . . . . . . 7  |-  ( ( B  e.  RR*  /\  B  = -oo )  ->  -e
( +oo +e B )  =  -e 0 )
6851adantl 482 . . . . . . . . 9  |-  ( ( B  e.  RR*  /\  B  = -oo )  ->  -e
B  = +oo )
6968oveq2d 6666 . . . . . . . 8  |-  ( ( B  e.  RR*  /\  B  = -oo )  ->  ( -oo +e  -e
B )  =  ( -oo +e +oo ) )
70 mnfaddpnf 12062 . . . . . . . 8  |-  ( -oo +e +oo )  =  0
7169, 70syl6eq 2672 . . . . . . 7  |-  ( ( B  e.  RR*  /\  B  = -oo )  ->  ( -oo +e  -e
B )  =  0 )
7261, 67, 713eqtr4a 2682 . . . . . 6  |-  ( ( B  e.  RR*  /\  B  = -oo )  ->  -e
( +oo +e B )  =  ( -oo +e  -e B ) )
73 xaddpnf2 12058 . . . . . . . 8  |-  ( ( B  e.  RR*  /\  B  =/= -oo )  ->  ( +oo +e B )  = +oo )
74 xnegeq 12038 . . . . . . . 8  |-  ( ( +oo +e B )  = +oo  ->  -e ( +oo +e B )  = 
-e +oo )
7573, 74syl 17 . . . . . . 7  |-  ( ( B  e.  RR*  /\  B  =/= -oo )  ->  -e
( +oo +e B )  =  -e +oo )
76 xnegcl 12044 . . . . . . . . 9  |-  ( B  e.  RR*  ->  -e
B  e.  RR* )
7776adantr 481 . . . . . . . 8  |-  ( ( B  e.  RR*  /\  B  =/= -oo )  ->  -e
B  e.  RR* )
78 xnegeq 12038 . . . . . . . . . . . 12  |-  (  -e B  = +oo  -> 
-e  -e
B  =  -e +oo )
7978, 22syl6eq 2672 . . . . . . . . . . 11  |-  (  -e B  = +oo  -> 
-e  -e
B  = -oo )
80 xnegneg 12045 . . . . . . . . . . . 12  |-  ( B  e.  RR*  ->  -e  -e B  =  B )
8180eqeq1d 2624 . . . . . . . . . . 11  |-  ( B  e.  RR*  ->  (  -e  -e B  = -oo  <->  B  = -oo ) )
8279, 81syl5ib 234 . . . . . . . . . 10  |-  ( B  e.  RR*  ->  (  -e B  = +oo  ->  B  = -oo )
)
8382necon3d 2815 . . . . . . . . 9  |-  ( B  e.  RR*  ->  ( B  =/= -oo  ->  -e
B  =/= +oo )
)
8483imp 445 . . . . . . . 8  |-  ( ( B  e.  RR*  /\  B  =/= -oo )  ->  -e
B  =/= +oo )
85 xaddmnf2 12060 . . . . . . . 8  |-  ( ( 
-e B  e. 
RR*  /\  -e B  =/= +oo )  -> 
( -oo +e  -e B )  = -oo )
8677, 84, 85syl2anc 693 . . . . . . 7  |-  ( ( B  e.  RR*  /\  B  =/= -oo )  ->  ( -oo +e  -e
B )  = -oo )
8722, 75, 863eqtr4a 2682 . . . . . 6  |-  ( ( B  e.  RR*  /\  B  =/= -oo )  ->  -e
( +oo +e B )  =  ( -oo +e  -e B ) )
8872, 87pm2.61dane 2881 . . . . 5  |-  ( B  e.  RR*  ->  -e
( +oo +e B )  =  ( -oo +e  -e B ) )
8988adantl 482 . . . 4  |-  ( ( A  = +oo  /\  B  e.  RR* )  ->  -e ( +oo +e B )  =  ( -oo +e  -e B ) )
90 simpl 473 . . . . . 6  |-  ( ( A  = +oo  /\  B  e.  RR* )  ->  A  = +oo )
9190oveq1d 6665 . . . . 5  |-  ( ( A  = +oo  /\  B  e.  RR* )  -> 
( A +e
B )  =  ( +oo +e B ) )
92 xnegeq 12038 . . . . 5  |-  ( ( A +e B )  =  ( +oo +e B )  ->  -e ( A +e B )  =  -e ( +oo +e B ) )
9391, 92syl 17 . . . 4  |-  ( ( A  = +oo  /\  B  e.  RR* )  ->  -e ( A +e B )  = 
-e ( +oo +e B ) )
94 xnegeq 12038 . . . . . . 7  |-  ( A  = +oo  ->  -e
A  =  -e +oo )
9594adantr 481 . . . . . 6  |-  ( ( A  = +oo  /\  B  e.  RR* )  ->  -e A  =  -e +oo )
9695, 22syl6eq 2672 . . . . 5  |-  ( ( A  = +oo  /\  B  e.  RR* )  ->  -e A  = -oo )
9796oveq1d 6665 . . . 4  |-  ( ( A  = +oo  /\  B  e.  RR* )  -> 
(  -e A +e  -e B )  =  ( -oo +e  -e B ) )
9889, 93, 973eqtr4d 2666 . . 3  |-  ( ( A  = +oo  /\  B  e.  RR* )  ->  -e ( A +e B )  =  (  -e A +e  -e
B ) )
99 simpr 477 . . . . . . . . . 10  |-  ( ( B  e.  RR*  /\  B  = +oo )  ->  B  = +oo )
10099oveq2d 6666 . . . . . . . . 9  |-  ( ( B  e.  RR*  /\  B  = +oo )  ->  ( -oo +e B )  =  ( -oo +e +oo ) )
101100, 70syl6eq 2672 . . . . . . . 8  |-  ( ( B  e.  RR*  /\  B  = +oo )  ->  ( -oo +e B )  =  0 )
102 xnegeq 12038 . . . . . . . 8  |-  ( ( -oo +e B )  =  0  ->  -e ( -oo +e B )  = 
-e 0 )
103101, 102syl 17 . . . . . . 7  |-  ( ( B  e.  RR*  /\  B  = +oo )  ->  -e
( -oo +e B )  =  -e 0 )
10432adantl 482 . . . . . . . . 9  |-  ( ( B  e.  RR*  /\  B  = +oo )  ->  -e
B  = -oo )
105104oveq2d 6666 . . . . . . . 8  |-  ( ( B  e.  RR*  /\  B  = +oo )  ->  ( +oo +e  -e
B )  =  ( +oo +e -oo ) )
106105, 64syl6eq 2672 . . . . . . 7  |-  ( ( B  e.  RR*  /\  B  = +oo )  ->  ( +oo +e  -e
B )  =  0 )
10761, 103, 1063eqtr4a 2682 . . . . . 6  |-  ( ( B  e.  RR*  /\  B  = +oo )  ->  -e
( -oo +e B )  =  ( +oo +e  -e B ) )
108 xaddmnf2 12060 . . . . . . . 8  |-  ( ( B  e.  RR*  /\  B  =/= +oo )  ->  ( -oo +e B )  = -oo )
109 xnegeq 12038 . . . . . . . 8  |-  ( ( -oo +e B )  = -oo  ->  -e ( -oo +e B )  = 
-e -oo )
110108, 109syl 17 . . . . . . 7  |-  ( ( B  e.  RR*  /\  B  =/= +oo )  ->  -e
( -oo +e B )  =  -e -oo )
11176adantr 481 . . . . . . . 8  |-  ( ( B  e.  RR*  /\  B  =/= +oo )  ->  -e
B  e.  RR* )
112 xnegeq 12038 . . . . . . . . . . . 12  |-  (  -e B  = -oo  -> 
-e  -e
B  =  -e -oo )
113112, 42syl6eq 2672 . . . . . . . . . . 11  |-  (  -e B  = -oo  -> 
-e  -e
B  = +oo )
11480eqeq1d 2624 . . . . . . . . . . 11  |-  ( B  e.  RR*  ->  (  -e  -e B  = +oo  <->  B  = +oo ) )
115113, 114syl5ib 234 . . . . . . . . . 10  |-  ( B  e.  RR*  ->  (  -e B  = -oo  ->  B  = +oo )
)
116115necon3d 2815 . . . . . . . . 9  |-  ( B  e.  RR*  ->  ( B  =/= +oo  ->  -e
B  =/= -oo )
)
117116imp 445 . . . . . . . 8  |-  ( ( B  e.  RR*  /\  B  =/= +oo )  ->  -e
B  =/= -oo )
118 xaddpnf2 12058 . . . . . . . 8  |-  ( ( 
-e B  e. 
RR*  /\  -e B  =/= -oo )  -> 
( +oo +e  -e B )  = +oo )
119111, 117, 118syl2anc 693 . . . . . . 7  |-  ( ( B  e.  RR*  /\  B  =/= +oo )  ->  ( +oo +e  -e
B )  = +oo )
12042, 110, 1193eqtr4a 2682 . . . . . 6  |-  ( ( B  e.  RR*  /\  B  =/= +oo )  ->  -e
( -oo +e B )  =  ( +oo +e  -e B ) )
121107, 120pm2.61dane 2881 . . . . 5  |-  ( B  e.  RR*  ->  -e
( -oo +e B )  =  ( +oo +e  -e B ) )
122121adantl 482 . . . 4  |-  ( ( A  = -oo  /\  B  e.  RR* )  ->  -e ( -oo +e B )  =  ( +oo +e  -e B ) )
123 simpl 473 . . . . . 6  |-  ( ( A  = -oo  /\  B  e.  RR* )  ->  A  = -oo )
124123oveq1d 6665 . . . . 5  |-  ( ( A  = -oo  /\  B  e.  RR* )  -> 
( A +e
B )  =  ( -oo +e B ) )
125 xnegeq 12038 . . . . 5  |-  ( ( A +e B )  =  ( -oo +e B )  ->  -e ( A +e B )  =  -e ( -oo +e B ) )
126124, 125syl 17 . . . 4  |-  ( ( A  = -oo  /\  B  e.  RR* )  ->  -e ( A +e B )  = 
-e ( -oo +e B ) )
127 xnegeq 12038 . . . . . . 7  |-  ( A  = -oo  ->  -e
A  =  -e -oo )
128127adantr 481 . . . . . 6  |-  ( ( A  = -oo  /\  B  e.  RR* )  ->  -e A  =  -e -oo )
129128, 42syl6eq 2672 . . . . 5  |-  ( ( A  = -oo  /\  B  e.  RR* )  ->  -e A  = +oo )
130129oveq1d 6665 . . . 4  |-  ( ( A  = -oo  /\  B  e.  RR* )  -> 
(  -e A +e  -e B )  =  ( +oo +e  -e B ) )
131122, 126, 1303eqtr4d 2666 . . 3  |-  ( ( A  = -oo  /\  B  e.  RR* )  ->  -e ( A +e B )  =  (  -e A +e  -e
B ) )
13260, 98, 1313jaoian 1393 . 2  |-  ( ( ( A  e.  RR  \/  A  = +oo  \/  A  = -oo )  /\  B  e.  RR* )  ->  -e ( A +e B )  =  (  -e
A +e  -e B ) )
1331, 132sylanb 489 1  |-  ( ( A  e.  RR*  /\  B  e.  RR* )  ->  -e
( A +e
B )  =  ( 
-e A +e  -e B ) )
Colors of variables: wff setvar class
Syntax hints:    -> wi 4    /\ wa 384    \/ w3o 1036    = wceq 1483    e. wcel 1990    =/= wne 2794  (class class class)co 6650   CCcc 9934   RRcr 9935   0cc0 9936    + caddc 9939   +oocpnf 10071   -oocmnf 10072   RR*cxr 10073   -ucneg 10267    -ecxne 11943   +ecxad 11944
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1722  ax-4 1737  ax-5 1839  ax-6 1888  ax-7 1935  ax-8 1992  ax-9 1999  ax-10 2019  ax-11 2034  ax-12 2047  ax-13 2246  ax-ext 2602  ax-sep 4781  ax-nul 4789  ax-pow 4843  ax-pr 4906  ax-un 6949  ax-cnex 9992  ax-resscn 9993  ax-1cn 9994  ax-icn 9995  ax-addcl 9996  ax-addrcl 9997  ax-mulcl 9998  ax-mulrcl 9999  ax-mulcom 10000  ax-addass 10001  ax-mulass 10002  ax-distr 10003  ax-i2m1 10004  ax-1ne0 10005  ax-1rid 10006  ax-rnegex 10007  ax-rrecex 10008  ax-cnre 10009  ax-pre-lttri 10010  ax-pre-lttrn 10011  ax-pre-ltadd 10012
This theorem depends on definitions:  df-bi 197  df-or 385  df-an 386  df-3or 1038  df-3an 1039  df-tru 1486  df-ex 1705  df-nf 1710  df-sb 1881  df-eu 2474  df-mo 2475  df-clab 2609  df-cleq 2615  df-clel 2618  df-nfc 2753  df-ne 2795  df-nel 2898  df-ral 2917  df-rex 2918  df-reu 2919  df-rab 2921  df-v 3202  df-sbc 3436  df-csb 3534  df-dif 3577  df-un 3579  df-in 3581  df-ss 3588  df-nul 3916  df-if 4087  df-pw 4160  df-sn 4178  df-pr 4180  df-op 4184  df-uni 4437  df-br 4654  df-opab 4713  df-mpt 4730  df-id 5024  df-po 5035  df-so 5036  df-xp 5120  df-rel 5121  df-cnv 5122  df-co 5123  df-dm 5124  df-rn 5125  df-res 5126  df-ima 5127  df-iota 5851  df-fun 5890  df-fn 5891  df-f 5892  df-f1 5893  df-fo 5894  df-f1o 5895  df-fv 5896  df-riota 6611  df-ov 6653  df-oprab 6654  df-mpt2 6655  df-er 7742  df-en 7956  df-dom 7957  df-sdom 7958  df-pnf 10076  df-mnf 10077  df-xr 10078  df-ltxr 10079  df-sub 10268  df-neg 10269  df-xneg 11946  df-xadd 11947
This theorem is referenced by:  xaddass2  12080  xposdif  12092  xadddi  12125  xrsxmet  22612
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