x³-5x²y²-xy-y³-()=2x³+y² 请问这题这么做?

问题描述:

x³-5x²y²-xy-y³-()=2x³+y² 请问这题这么做?

x³-5x²y²-xy-y³-()=2x³+y²
()=x³-5x²y²-xy-y³-(2x³+y²)
=-x³-5x²y²-xy-y³-y²