(a+b+c)^2=a^2+b^2+c^2+2ab+2bc+2ac (-a-b-c)^2=a^2+b^2+c^2+2ab+2bc+2ac (a+c-b)^2=a^2+b^2+c^2-2ab-2bc+2ac (a-b-c)^2=a^2+b^2+c^2-2ab+2bc-2ac 求采纳
含三个未知数的三个数的平方怎么算？求公式
(a+b+c)^2=a^2+b^2+c^2+2ab+2bc+2ac (-a-b-c)^2=a^2+b^2+c^2+2ab+2bc+2ac (a+c-b)^2=a^2+b^2+c^2-2ab-2bc+2ac (a-b-c)^2=a^2+b^2+c^2-2ab+2bc-2ac 求采纳