已知a=-1,求[(a+3)分之（a²-a-6）]²乘以[(a²+a-6)分之（a-3)]的负二次方

已知a=-1,求[(a+3)分之（a²-a-6）]²乘以[(a²+a-6)分之（a-3)]的负二次方
已知a=-1,求[(a+3)分之（a²-a-6）]²乘以[(a²+a-6)分之（a-3)]的负二次方

已知a=-1,求[(a+3)分之（a²-a-6）]²乘以[(a²+a-6)分之（a-3)]的负二次方
[(a+3)分之（a²-a-6）]²乘以[(a²+a-6)分之（a-3)]的负二次方
=[(a-3)(a+2)/(a+3)×(a+3)(a-2)/(a-3)]²
=[(a+2)(a-2)]²
=(a²-4)²
=a的4次方-8a²+16

[(a²-a-6)/(a+3)]²*[(a-3)/(a²+a-6)]^(-2)
=[(a-3)(a+2)/(a+3)]²*[(a²+a-6)/(a-3)]²
=[(a-3)(a+2)/(a+3)*(a²+a-6)/(a-3)]²
=[(a-3)(a+2)/(a+3)*(a+3)(a-2)/(a-3)]²
=[(a+2)(a-2)]²
=(a²-4)²
=[(-1)²-4]²
=[1-4]²
=(-3)²
=9