关于初二几道分式的题!计算①.4a^b/3cd^ · 5c^d/4ab^ ÷ 2abc/3d②.81-a^/a^ + 6a+9 ÷ a-9/2a+6 · a+3/a+9

有点不太明白,但是还是试试1.(4a^2b/3cd^2)*(5c^2d/4ab^2)/(2abc/3d)=(4a^2b*5c^2d*3d)/(3cd^2*4ab^2*2abc)=(60a^2bc^2d^2)/(24a^2b^3c^2d^2)=5/(2b^2)2.（81-a²）/(a²+6a+9)÷(a-9)/(2a+6)×(a+3)/(a+9)=...