50 баллов.
Нужно ПОДРОБНОЕ решение.
=1-4*3=1-12=-11;
б) (2sqrt(3)-sqrt(2))(3sqrt(2)+2sqrt(3))=
=2sqrt(3)*3sqrt(2)-sqrt(2)*3sqrt(2)+2sqrt(3)*2sqrt(3)-sqrt(2)*2sqrt(3)=
=6sqrt(3*2)-3*2+2*2*3-2sqrt(2*3)=6sqrt(6)-6+12-2 sqrt(6)=
=sqrt(6)*(6-2)+(12-6)=4sqrt(6)+6;
в) (3-sqrt(3))(2-sqrt(3))=3*2-sqrt(3)*2-3*sqrt(3)+sqrt(3)*sqrt(3)=
=6-2sqrt(3)-3sqrt(3)+3=(6+3)-sqrt(3)*(2+3)=9-5sqrt(3);
г) (sqrt(5)+sqrt(8))(sqrt(5)+3sqrt(2))=(sqrt(5)+2sqrt(2))(sqrt(5)+3sqrt(2))=
=sqrt(5)*sqrt(5)+2sqrt(2)*sqrt(5)+sqrt(5)*3sqrt(2)+2sqrt(2)*3sqrt(2)=
=5+2sqrt(10)+3sqrt(10)+12=17+5sqrt(10);
д) (5sqrt(2)-sqrt(125))(sqrt(125)-sqrt(2))-sqrt(250)=
=(5sqrt(2)-sqrt(25*5))(sqrt(25*5)-sqrt(2))-sqrt(25*10)=
=(5sqrt(2)-5sqrt(5))(5sqrt(5)-sqrt(2))-5sqrt(10)=
=5sqrt(2)*5sqrt(5)-5sqrt(5)*5sqrt(5)-5sqrt(2)*sqrt(2)+5sqrt(5)*sqrt(2)-5sqrt(10)=
=25sqrt(2*5)-5*5*5-5*2+5sqrt(5*2)-5sqrt(10)=
=25sqrt(10)-125-10+5sqrt(10)-5sqrt(10)=25sqrt(10)-135.