急(2a^3-1/6a^2b+3a)/(-1/3a)(2a^3-1/6a^2b+3a)/(-1/3a)(x-2)(x+2)-(x+1)(x-3)(1-3y)(1+3y)(1+9y^2)(ab+1)^2-(ab-1)^2
问题描述:
急(2a^3-1/6a^2b+3a)/(-1/3a)
(2a^3-1/6a^2b+3a)/(-1/3a)
(x-2)(x+2)-(x+1)(x-3)
(1-3y)(1+3y)(1+9y^2)
(ab+1)^2-(ab-1)^2
答