(9a²+6a+1)分之(a²-4a+4)÷(3a+1)分之(6-3a)

(9a²+6a+1)分之(a²-4a+4)÷(3a+1)分之(6-3a)
(9a²+6a+1)分之(a²-4a+4)÷(3a+1)分之(6-3a)

(9a²+6a+1)分之(a²-4a+4)÷(3a+1)分之(6-3a)
(9a²+6a+1)=(3a+1)²,(a²-4a+4)=(a-2)²,(6-3a)=3(2-a)=-3(a-2).所以(9a²+6a+1)分之(a²-4a+4)÷(3a+1)分之(6-3a)=(3a+1)²分之(a-2)²÷(3a+1)分之-3(a-2)=(3a+1)²分之(a-2)²* -3(a-2)分之(3a+1)=-(9a+3)分之（a-2）