1.-a^5X(-a^6)Xa^6=a^17
2.若（x-2)²+（y+3)²=0,則（x+y)²=多少?
得出,x=2,y=-3,（x+y)²=(2-3)^2=1
3 B.(-ab)²=a²b²正確
4 m²+n²-2m-4n+8=（m-1）^2+(n-2)^2+3 總是正數(shù)
5x(x-y)²-y(y-x)²=x(x-y)²-y(x-y)²=(x-y)(x-y)²=(x-y)^3
6 1.[（xy²）²]³+[（-xy²）²]³=[（x^2y^4]³+[（x^2y^4]³=x^6y^12+x^6y^12=2x^6y^12
2.（-1/2a²b）（2/3b²-1/3a+1/4)
=-1/2a²bX2/3b²-(-1/2a²bX1/3a)+(-1/2a²bX1/4)
=-1/3a²b^3+1/6a^3b-1/8a²b
3.因式分解 25（a+b)²-16（a-b)² 平方差公式
=[5(a+b)+4(a-b)][5(a+b)-4(a-b)]
= [5a+5b+4a-4b][5a+5b-4a+4b]
=(9a+b)(a+9b)