合并同类项:3x³-4(x²-x³+1)-5x²

问题描述:

合并同类项:3x³-4(x²-x³+1)-5x²
合并同类项:6a²+3b²-5a²-2b²

3x³-4(x²-x³+1)-5x²
=3x^3-4x^2+4x^3-4-5x^2
=7x^3-9x^2-4
6a²+3b²-5a²-2b²
=(6-5)a^2+(3-2)b^2
=a^2+b^2