1.-2X(X+3)+(X+3)^2+2(X-3)/(X+3)^2 (X-3)=X+1/(X+3)^2=X+1/X^2+6X+9
2.X-3+X-1+X-2/(X-3)(X-2)(X-1)=3/(X-2)(X-1)=3/X^2-3X+2
3.X+1+X-1/(1+X)(1-X+) +2/1+x² + 4/1+x²=2X(1+X^2)+6(1-X^2)/(1+X^2)(1-X^2)=2X^3-6X^2+2X+6/1-4X^4
4.4(a+b)^2+3b(a-b)+ab+7b^2/2(a+b)(a-b)=2*(49/4)^2+49/4*(-31/4)+3(-31/4)^2/180=2083/8