a^2b^2-1分之ab-2a^2b^2+a^3b^3 ab=-2

a^2b^2-1分之ab-2a^2b^2+a^3b^3 ab=-2




a-b=5,ab=3,a*3b-2a*2b*2+ab*3=?
塊塊說明:如a*3b表示a的3次方乘b


a^3b-2a^2b^2+ab^3
=ab(a^2-2ab+b^2)
=ab(a-b)^2
=3*25
=75