Question

已知a+2b=0，求a的立方+3a平方b+2ab平方的值

Answer 1

a的立方+3a平方b+2ab平方
=a^2(a+2b+b)+2ab^2
=a^2b+2ab^2
=ab(a+2b)
=0

Answer 2

a的立方+3a平方b+2ab²
=a(a²+3ab+2b²)
=a(a+b)(a+2b)
=a(a+b)*0
=0

Answer 3

a的立方+3a平方b+2ab²
=a(a²+3ab+b²)
=a(a+b)(a+2b)
=0

Answer 4

等于0 提出个a来，括号里得0

Answer 5

a^3+3b*a^2+2a*b^2=a[a^2+3ab+2b^2]
=a[a(a+3b)+2b^2]
=a[a(a+2b+b)+2b^2]
=a(ab+2b^2)
=ab(a+2b)
=0
这种类型一般都是先局部化简，中间能代已知条件就带进去，一步步不断的带入已知条件。