题目(1)(1)(1)当a=−1a=-1a=−1时,求代数式a3−3a2+2a+4a^{3}-3a^{2}+2a+4a3−3a2+2a+4的值.(2)(2)(2)已知x+y=2x+y=2x+y=2,x−y=−1x-y=-1x−y=−1,求代数式(x+y)2−3(x−y)3+1\left(x+y\right)^{2}-3\left(x-y\right)^{3}+1(x+y)2−3(x−y)3+1的值.知识点：不等式的解集章节：方程与不等式 / 不等式与不等式组
