a)β3*3β2-5β6*4+4β3*2β2-4β2*3β3=
=3β6-20β6+8β6-12β6=
=11β6-32β6=
=-21β6
b)β6+2β3*β3-2β2*3β3+2β2*5β2+β3*4β2+β3*β3=
=β6+6-6β6+20+4β6+3=
=29-β6
2)(-β48+β200) / (2β3+5β2)=
=(-4β3+10β2) / (2β3+5β2)=
=-2(2β3-5β2) / (2β3+5β2)=
=-2(2β3-5β2)(2β3-5β2) / (2β3+5β2)(2β3-5β2)=
=-2(36-20β6+100) / (12-50)=
=-2(36-20β6) / (-38)=
=(36-20β6) / 19