Ответ:

Объяснение:

а)а2-25/a+3-1/a2+5a-a+5/a2-3a=(a-5)(a+5)/a+3*1/a(a-3)=a-5/a(a-3)-a+5/a(a-3)=(a-5)*(a-3)-(a+5)*(a+3)/a(a+3)(a-3)=a2-3a-5a+15-a2-3a-5a-15/a(a+3)(a-3)=-16a/a(a2-9)=-16/a2-9

б)1-2x/2x+1+x2+3x/4x2-1*3+x/4x+2=1-2x/2x+1+x(x+3)/(2x-1)(2x+1)*2(2x+1)/3+x=1-2x/2x+1+2x/2x-1=(1-2x)(2x-1)+2x*(2x+1)/(2x+1)(2x-1)=2x-1-4x2+2x+4x2+2x/(2x+1)*(2x-1)=6x-1/4x2-1

в)b-c/a+b-ab-b2/a2-ac*a2-c2/a2-b2=b-c/a+b-b(a-b)/a(a-c)*(a-c)(a+c)/(a-b)(a+b)=b-c/a+b-b(a+c)/a(a+b)=(b-c)*a-b*(a+c)/a(a+b)=ab-ac-ba-bc/a(a+b)=-ac-bc/a(a+b)=-c(a+b)/a(a+b)=-c/a

г)a2-4/x2-9:a2-2a/xy+3y+2-y/x-3=(a-2)(a+2)/(x-3)(x+3)*y(x+3)/a(a-2)-2-y/x-3=y(a+2)+(2-y)*a/a(x-3)=ya+2y+2a-ya/a(x-3)=2(y+a)/a(x-3)