; TeX output 1997.02.17:1458y?MK`y cmr10ThisUUisanexampleottheuseofthe cmmi10aٓRcmr72S+8b2C=c28(1)>NowUUwestartsub-numbGering.d2S+8e2C=f28(2a)>W*eUUcanrefertoequation1,2and2a.Wg[ٟ2,+8h2C=i2(2b)>ThisUUwasequation2b.Tvx =Ұy+8z(2c)Ru =Ұv+8w(2d)>ThisUUwasexpression2c,consistingofparts2cand2d. MNowUUletsstartam#R cmss10subGeqnarrayxenvironment.Tvx =Ұy+8z8(3a)Ru =Ұv+8w(3b)>ThisUUwasequation3,withparts3aand3b.1*;ym#R cmss10 cmmi10K`y cmr10ٓRcmr7Q