Найти пределы функций в точке x0 используя свойства пределов

1) limx→-1-x2+x+2x2+x-6=limx→-1--12+-1+2-12+-1-6=0-6=0
limx→-3-x2+x+2x2+x-6=limx→-1--32+-3+2-32+-3-6=-100=-∞
limx→2-x2+x+2x2+x-6=00=limx→2-x-2x+1x-2x+3=limx→2-x+1x+3=-35
limx→∞-x2+x+2x2+x-6=∞∞=limx→∞-x2x2+xx2+2x2x2x2+xx2-6x2=limx→∞-1+1x→0+2x2→01+1x→0-6x2→0=-1
2) limx→51+3x-2x+6x2-5x=00=limx→51+3x-2x+61+3x+2x+6x2-5x1+3x+2x+6=limx→51+3x-2x-6xx-51+3x+2x+6=limx→5x-5xx-51+3x+2x+6=limx→51x1+3x+2x+6=140
3) limx→05sin23xx*tg2x=00=limx→05sin23xx*sin2xcos2x=limx→05*9x2*sin23x9x2x*2x*sin2x2x*cos2x=sin23x9x2~1sin2x2x~1=limx→05*9x2x*2xcos2x=limx→045x22x2cos2x=limx→045x2*cos2x2x2=limx→045cos2x2=452
4) limx→0etg24x-131-tg2x-11-cossin2xln1-tgπx=00=etg24x-1~tg24x1-cossin2x~sin22x2ln1-tgπx~-tgπx=limx→0tg24x31-tg2x-1sin22x2*-tgπx=limx→02tg24x31-tg2x-1sin22x*-tgπx=sin22x~4x2tgπx~πxtg24x~16x2tg2x~2x=limx→02*16x231-tg2x-14x2*-πx=limx→0831-2x-1-πx=limx→0831-2x-131-2x2+31-2x+1-πx31-2x2+31-2x+1=limx→08*-2x-πx31-2x2+31-2x+1=limx→0-16x-πx31-2x2+31-2x+1=limx→0-16-π31-2x2+31-2x+1=163π