1.(-3+x)(-3-x)=___ 2.(x-3)(-x-3)=____ 3.(a+___)(a-____)=a²-0.25
问题描述:
1.(-3+x)(-3-x)=___ 2.(x-3)(-x-3)=____ 3.(a+___)(a-____)=a²-0.25
答
(-3+x)(-3-x)= 9-x^2
(x-3)(-x-3)=9-x^2
(a+0.5)(a-0.5)=a²-0.25