Question

求大神来解！！！急急急！！

Answer 1

原式=a(a²-b²)
=a(a+b)(a-b)

原式=2-3+(-2)
= -3

原式=[(a-2b)(a-2b+a+2b)-2a(2a-b)]÷2a
=[2a(a-2b)-2a(2a-b)]÷2a
=[2a(a-2b-2a+b)]÷2a
=-a-b
代入，得 = -a-b = -2+1/2 = -3/2

Answer 2

1:a(a-b)(a+b)
2:2-3+(-2)=-3
3:=[(a-2b)((a-2b)+(a+2b)-2a(2a+b)]/2a
=[2a(a-2b)-2a(2a+b)]/2a
=2a[(a-2b)-(2a+b)]/2a
=(a-2b)-(2a+b)
=-(a+b)
=-(2-1/2)
=-3/2