Question

-4a^3+16a^2b-26ab^2

Answer 1

-4a^3+16a^2b-16ab^2

= -4a(a^2-4ab+4b^2)

= -4a(a-2b)^2

【问题补充：是26不是16】

-4a^3+16a^2b-26ab^2

= -2a{ 2a2^2 - 8ab + 13 b^2 }

括号内判别式△=(-8b)^2-4*2*13b^2=64b^2-104b^2=-40b^2＜0,∴括号内不能继续分解

∴-4a^3+16a^2b-26ab^2= -2a{ 2a2^2 - 8ab + 13 b^2 }