Найти пределы функций не пользуясь правилом Лопиталя

Limx→∞x-3x2+2x35x3-6x2+3x+2=∞∞=limx→∞xx3-3x2x3+2x3x35x3x3-6x2x3+3xx3+2x3=limx→∞1x2→0-3x→0+25-6x→0+3x2→0+2x3→0=25
б) limx→-3x2+2x-3x3+4x2+3x=00=limx→-3x+3x-1x2+4x+3x=limx→-3x+3x-1x+3x+1x=limx→-3x-1x+1x=-3-1-3+1*-3=-46=-23
в) limx→41+2x-3x2-3x-4=00=limx→41+2x-31+2x+3x+1x-41+2x+3=limx→41+2x-9x+1x-41+2x+3=limx→42x-8x+1x-41+2x+3=limx→42x-4x+1x-41+2x+3=limx→42x+11+2x+3=24+11+2*4+3=230=115
г) limx→0x2*ctg2xtg5x=00=limx→0x2*cos2xsin2xsin5xcos5x=limx→0x2*cos2x*cos5xsin2x*sin5x=sin2x~2xtg5x~5x=limx→0x2*cos2x*cos5x2x*5x=limx→0x2*cos2x*cos5x10x2=limx→0cos2x*cos5x10=cos2*0*cos5*010=110
д) limx→32x-5xx2-9=1∞=y=x-3;y→0x=y+3;x→3=limy→02*y+3-5y+3y+32-9=limy→02y+6-5y+3y2+6y+9-9=limy→02y+1y+3y2+6y=limy→01+112y12ye2yy+3y2+6y=elimy→02yy+3 y2+6y=elimy→02yy+3 yy+6=elimy→02y+3 y+6=e66=e