let x1, x2, x3, x4, x5, x6, x7, x8, y1, y2, y3, y4, y5, y6, y7, y8 be set ; ( [x1,x2,x3,x4,x5,x6,x7,x8] = [y1,y2,y3,y4,y5,y6,y7,y8] implies ( x1 = y1 & x2 = y2 & x3 = y3 & x4 = y4 & x5 = y5 & x6 = y6 & x7 = y7 & x8 = y8 ) )
assume A1:
[x1,x2,x3,x4,x5,x6,x7,x8] = [y1,y2,y3,y4,y5,y6,y7,y8]
; ( x1 = y1 & x2 = y2 & x3 = y3 & x4 = y4 & x5 = y5 & x6 = y6 & x7 = y7 & x8 = y8 )
then
[x1,x2,x3,x4,x5,x6,x7] = [y1,y2,y3,y4,y5,y6,y7]
by ZFMISC_1:27;
hence
( x1 = y1 & x2 = y2 & x3 = y3 & x4 = y4 & x5 = y5 & x6 = y6 & x7 = y7 & x8 = y8 )
by A1, Th83, ZFMISC_1:27; verum