1). 2/b - 2/2+b =(4+2b-2b)/(b ²+2b)=4/(b ²+2b)
2). 3/(y ²-3y) + 1/(y-3) = (3+y+3)/(y ²-3y)=
(y+6)/(y ²-3y)
3). 1/(m-2) - 4/(m ²-4)=(m+4-4)/(m ²-4)=
m/(m ²-4)
4). 7-(3-5a)/(a+1)=(7a+7-3+5a)/(a+1)=
(12a-4)/(a+1)
5). 1/(y-3) - 6/(y ²-9)=(y+3-6)/(y ²-9)=
(y-3)/(y-3)(y+3)=1/(y+3)
6). (4c-4d)/(c ²-2cd+d ²)-3/(c-d)=
(4c-4d-3c+3d)/(c-d) ²=(c-d)/(c-d) ²=1/(c-d)
7). (2/(a-2) - 3/(a+2))×(4-a ²)/(10a-a ²)=
(2a+4-3a+6)/(a-2)(a+2) × (2-a)(2+a)/a(10-a)=
_(10-a)/a(10-a)=-1/a