let i be Nat; :: thesis: for G being Go-board st 1 <= i & i < len G & 1 < width G holds
LSeg ((((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1)))) - |[0,1]|),((1 / 2) * ((G * (i,1)) + (G * ((i + 1),2))))) c= ((Int (cell (G,i,0))) \/ (Int (cell (G,i,1)))) \/ {((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1))))}

let G be Go-board; :: thesis: ( 1 <= i & i < len G & 1 < width G implies LSeg ((((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1)))) - |[0,1]|),((1 / 2) * ((G * (i,1)) + (G * ((i + 1),2))))) c= ((Int (cell (G,i,0))) \/ (Int (cell (G,i,1)))) \/ {((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1))))} )
assume that
A1: 1 <= i and
A2: i < len G and
A3: 1 < width G ; :: thesis: LSeg ((((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1)))) - |[0,1]|),((1 / 2) * ((G * (i,1)) + (G * ((i + 1),2))))) c= ((Int (cell (G,i,0))) \/ (Int (cell (G,i,1)))) \/ {((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1))))}
set p1 = G * (i,1);
set q2 = G * ((i + 1),1);
set q3 = G * ((i + 1),2);
set r = 1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1);
A4: ( i + 1 >= 1 & i + 1 <= len G ) by A2, NAT_1:11, NAT_1:13;
A5: 0 + (1 + 1) <= width G by A3, NAT_1:13;
then A6: (G * ((i + 1),1)) `1 = (G * ((i + 1),2)) `1 by A4, GOBOARD5:2;
A7: (G * ((i + 1),1)) `2 = (G * (1,(0 + 1))) `2 by A3, A4, GOBOARD5:1
.= (G * (i,1)) `2 by A1, A2, A3, GOBOARD5:1 ;
then (G * (i,1)) `2 < (G * ((i + 1),2)) `2 by A5, A4, GOBOARD5:4;
then A8: ((G * ((i + 1),2)) `2) - ((G * (i,1)) `2) > 0 by XREAL_1:50;
then 1 < ((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1 by XREAL_1:29, XREAL_1:129;
then A9: 1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1) < 1 by XREAL_1:212;
set I1 = Int (cell (G,i,0));
set I2 = Int (cell (G,i,1));
A10: LSeg ((((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1)))) - |[0,1]|),((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1))))) c= (Int (cell (G,i,0))) \/ {((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1))))} by A1, A2, Th46;
A11: ((Int (cell (G,i,0))) \/ (Int (cell (G,i,1)))) \/ {((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1))))} = (Int (cell (G,i,0))) \/ ((Int (cell (G,i,1))) \/ ({((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1))))} \/ {((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1))))})) by XBOOLE_1:4
.= (Int (cell (G,i,0))) \/ (((Int (cell (G,i,1))) \/ {((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1))))}) \/ {((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1))))}) by XBOOLE_1:4
.= ((Int (cell (G,i,0))) \/ {((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1))))}) \/ ((Int (cell (G,i,1))) \/ {((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1))))}) by XBOOLE_1:4 ;
A12: ((((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * ((1 / 2) * (G * ((i + 1),1)))) + ((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * ((1 / 2) * (G * ((i + 1),2))))) - ((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * |[0,1]|)) `1 = ((((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * ((1 / 2) * (G * ((i + 1),1)))) + ((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * ((1 / 2) * (G * ((i + 1),2))))) `1) - (((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * |[0,1]|) `1) by Lm2
.= ((((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * ((1 / 2) * (G * ((i + 1),1)))) + ((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * ((1 / 2) * (G * ((i + 1),2))))) `1) - (|[((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * 0),((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * 1)]| `1) by EUCLID:58
.= ((((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * ((1 / 2) * (G * ((i + 1),1)))) + ((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * ((1 / 2) * (G * ((i + 1),2))))) `1) - 0 by EUCLID:52
.= (((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * ((1 / 2) * (G * ((i + 1),1)))) `1) + (((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * ((1 / 2) * (G * ((i + 1),2)))) `1) by Lm1
.= ((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * (((1 / 2) * (G * ((i + 1),1))) `1)) + (((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * ((1 / 2) * (G * ((i + 1),2)))) `1) by Lm3
.= ((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * (((1 / 2) * (G * ((i + 1),1))) `1)) + ((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * (((1 / 2) * (G * ((i + 1),2))) `1)) by Lm3
.= ((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * ((1 / 2) * ((G * ((i + 1),1)) `1))) + ((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * (((1 / 2) * (G * ((i + 1),2))) `1)) by Lm3
.= ((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * ((1 / 2) * ((G * ((i + 1),1)) `1))) + ((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * ((1 / 2) * ((G * ((i + 1),1)) `1))) by A6, Lm3
.= ((1 / 2) * (G * ((i + 1),1))) `1 by Lm3 ;
A13: ((((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * ((1 / 2) * (G * (i,1)))) + ((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * ((1 / 2) * (G * (i,1))))) + ((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * ((1 / 2) * (G * ((i + 1),1))))) + ((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * ((1 / 2) * (G * ((i + 1),2)))) = ((((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * ((1 / 2) * (G * (i,1)))) + ((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * ((1 / 2) * (G * ((i + 1),1))))) + ((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * ((1 / 2) * (G * (i,1))))) + ((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * ((1 / 2) * (G * ((i + 1),2)))) by RLVECT_1:def 3
.= (((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * ((1 / 2) * (G * (i,1)))) + ((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * ((1 / 2) * (G * ((i + 1),1))))) + (((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * ((1 / 2) * (G * (i,1)))) + ((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * ((1 / 2) * (G * ((i + 1),2))))) by RLVECT_1:def 3
.= (((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * ((1 / 2) * (G * (i,1)))) + ((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * ((1 / 2) * (G * ((i + 1),1))))) + ((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * (((1 / 2) * (G * (i,1))) + ((1 / 2) * (G * ((i + 1),2))))) by RLVECT_1:def 5
.= ((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * (((1 / 2) * (G * (i,1))) + ((1 / 2) * (G * ((i + 1),1))))) + ((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * (((1 / 2) * (G * (i,1))) + ((1 / 2) * (G * ((i + 1),2))))) by RLVECT_1:def 5
.= ((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * (((1 / 2) * (G * (i,1))) + ((1 / 2) * (G * ((i + 1),1))))) + ((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * ((1 / 2) * ((G * (i,1)) + (G * ((i + 1),2))))) by RLVECT_1:def 5
.= ((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * ((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1))))) + ((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * ((1 / 2) * ((G * (i,1)) + (G * ((i + 1),2))))) by RLVECT_1:def 5 ;
A14: (((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * ((1 / 2) * ((G * ((i + 1),2)) `2))) - ((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * ((1 / 2) * ((G * ((i + 1),1)) `2)))) + (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) = (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * ((i + 1),1)) `2))) + 1)
.= 1 by A7, A8, XCMPLX_1:106 ;
((((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * ((1 / 2) * (G * ((i + 1),1)))) + ((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * ((1 / 2) * (G * ((i + 1),2))))) - ((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * |[0,1]|)) `2 = ((((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * ((1 / 2) * (G * ((i + 1),1)))) + ((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * ((1 / 2) * (G * ((i + 1),2))))) `2) - (((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * |[0,1]|) `2) by Lm2
.= ((((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * ((1 / 2) * (G * ((i + 1),1)))) + ((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * ((1 / 2) * (G * ((i + 1),2))))) `2) - (|[((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * 0),((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * 1)]| `2) by EUCLID:58
.= ((((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * ((1 / 2) * (G * ((i + 1),1)))) + ((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * ((1 / 2) * (G * ((i + 1),2))))) `2) - (1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) by EUCLID:52
.= ((((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * ((1 / 2) * (G * ((i + 1),1)))) `2) + (((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * ((1 / 2) * (G * ((i + 1),2)))) `2)) - (1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) by Lm1
.= (((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * (((1 / 2) * (G * ((i + 1),1))) `2)) + (((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * ((1 / 2) * (G * ((i + 1),2)))) `2)) - (1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) by Lm3
.= (((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * (((1 / 2) * (G * ((i + 1),1))) `2)) + ((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * (((1 / 2) * (G * ((i + 1),2))) `2))) - (1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) by Lm3
.= (((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * ((1 / 2) * ((G * ((i + 1),1)) `2))) + ((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * (((1 / 2) * (G * ((i + 1),2))) `2))) - (1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) by Lm3
.= (((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * ((1 / 2) * ((G * ((i + 1),1)) `2))) + ((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * ((1 / 2) * ((G * ((i + 1),2)) `2)))) - (1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) by Lm3
.= ((1 / 2) * (G * ((i + 1),1))) `2 by A14, Lm3 ;
then A15: (((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * ((1 / 2) * (G * ((i + 1),1)))) + ((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * ((1 / 2) * (G * ((i + 1),2))))) - ((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * |[0,1]|) = |[(((1 / 2) * (G * ((i + 1),1))) `1),(((1 / 2) * (G * ((i + 1),1))) `2)]| by A12, EUCLID:53
.= (1 / 2) * (G * ((i + 1),1)) by EUCLID:53 ;
(1 / 2) * ((G * (i,1)) + (G * ((i + 1),1))) = ((1 / 2) * (G * (i,1))) + ((1 / 2) * (G * ((i + 1),1))) by RLVECT_1:def 5
.= (((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) + (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * ((1 / 2) * (G * (i,1)))) + ((1 / 2) * (G * ((i + 1),1))) by RLVECT_1:def 8
.= (((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * ((1 / 2) * (G * (i,1)))) + ((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * ((1 / 2) * (G * (i,1))))) + ((1 / 2) * (G * ((i + 1),1))) by RLVECT_1:def 6
.= ((((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * ((1 / 2) * (G * (i,1)))) + ((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * ((1 / 2) * (G * (i,1))))) + (((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * ((1 / 2) * (G * ((i + 1),1)))) + ((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * ((1 / 2) * (G * ((i + 1),2)))))) - ((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * |[0,1]|) by A15, RLVECT_1:def 3
.= (((((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * ((1 / 2) * (G * (i,1)))) + ((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * ((1 / 2) * (G * (i,1))))) + ((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * ((1 / 2) * (G * ((i + 1),1))))) + ((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * ((1 / 2) * (G * ((i + 1),2))))) - ((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * |[0,1]|) by RLVECT_1:def 3
.= ((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * ((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1))))) + (((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * ((1 / 2) * ((G * (i,1)) + (G * ((i + 1),2))))) - ((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * |[0,1]|)) by A13, RLVECT_1:def 3
.= ((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * ((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1))))) + (- (((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * |[0,1]|) - ((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * ((1 / 2) * ((G * (i,1)) + (G * ((i + 1),2))))))) by RLVECT_1:33
.= ((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * ((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1))))) - (((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * |[0,1]|) - ((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * ((1 / 2) * ((G * (i,1)) + (G * ((i + 1),2))))))
.= (((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * ((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1))))) - ((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * |[0,1]|)) + ((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * ((1 / 2) * ((G * (i,1)) + (G * ((i + 1),2))))) by RLVECT_1:29
.= ((1 - (1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1))) * (((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1)))) - |[0,1]|)) + ((1 / (((1 / 2) * (((G * ((i + 1),2)) `2) - ((G * (i,1)) `2))) + 1)) * ((1 / 2) * ((G * (i,1)) + (G * ((i + 1),2))))) by RLVECT_1:34 ;
then (1 / 2) * ((G * (i,1)) + (G * ((i + 1),1))) in LSeg ((((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1)))) - |[0,1]|),((1 / 2) * ((G * (i,1)) + (G * ((i + 1),2))))) by A8, A9;
then A16: LSeg ((((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1)))) - |[0,1]|),((1 / 2) * ((G * (i,1)) + (G * ((i + 1),2))))) = (LSeg ((((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1)))) - |[0,1]|),((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1)))))) \/ (LSeg (((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1)))),((1 / 2) * ((G * (i,1)) + (G * ((i + 1),2)))))) by TOPREAL1:5;
(0 + 1) + 1 = 0 + (1 + 1) ;
then LSeg (((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1)))),((1 / 2) * ((G * (i,1)) + (G * ((i + 1),2))))) c= (Int (cell (G,i,1))) \/ {((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1))))} by A1, A2, A3, Th43;
hence LSeg ((((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1)))) - |[0,1]|),((1 / 2) * ((G * (i,1)) + (G * ((i + 1),2))))) c= ((Int (cell (G,i,0))) \/ (Int (cell (G,i,1)))) \/ {((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1))))} by A16, A10, A11, XBOOLE_1:13; :: thesis: verum