若a+b=3,a^2b+ab^2=-30,则a的3次方+b的3次方的值是多少?

若a/b=2 则a*a-ab+b*b/a*a+b*b等于? 若a/b+b/a=3,求a^2+ab+b^2/a^2-ab+b^2的值 ab/a+b=3 a-2ab+b/2a-3ab+2b? 若a/b=2,求分式a*a+ab-b*b/a*a-2ab+2b*b a^3-ab^2 =a （a^2 -b^2) =a(a+b)(a-b) 若ab不等于0,且3a=b,求代数式b/3a-(-b)/a-a/2b/(-b) 若a+b=3 ab=-2,求a+ab+ab+b的值 若a-b=3ab,则2a-ab-2b/a+2ab-b=? 若a+b-ab=0,则(3a+3b-ab)/(2a+2b+ab)= 若a-b=3ab,求2a-ab-2b除以a+2ab-b的值 若a+b=3,ab=-2,求(5a-5b-ab)-(4a-6b-3ab) 已知3a*a+ab-2b*b=0(a不等于0,b不等于0),求a/b-b/a-(a*a+b*b)/ab的值. 若a-b=4,ab=1,求(-2ab+2a+3b)-(3ab+2b-2a)-(a+4b+ab)的值 若a-b=4 ab=1 求（-2ab+2a+3b)-(3ab+2b-2a)-(a+4b+ab)的值 若a-b=4 ab=1 求（-2ab+2a+3b)-(3ab+2b-2a)-(a+4b+ab)的值 b/a+a/b=3,求2ab/(a*a+b*b)-(3a*a+ab+3b*b)/2ab的值 已知a*a-ab=3,ab+b*b=-5,求代数式a*a+b*b与a*a-2ab-b*b的值 若A=a+2b B=-b+3a 求2AB