因式分解3x^2-10xy-5y^2=?

分类: 作业答案 • 2021-12-31 11:50:28

问题描述：

答

3x²-10xy-5y²=3[x²-10xy/3+(5y/3)²]-3×25y²/9-5y²=3(x-5y/3)²-40y²/3=3[(x-5y/3)²-(2√10y/3)²]=3(x-5y/3+2√10y/3)(x-5y/3-2√10y/3)