國中二年級數學,因式分解 X平方-Y平方-2Y-1 =?
回答 (2)
2017-01-30 7:33 am
Sol
x^2－y^2－2y－1
=x^2－(y+2+2y+1)
=x^2－(y+1)^2
=[x－(y+1)];{x+(y+1)}
=(x－y－1)(x+y+1)
x^2－y^2－2y－1
=x^2－(y+2+2y+1)
=x^2－(y+1)^2
=[x－(y+1)];{x+(y+1)}
=(x－y－1)(x+y+1)
收錄日期: 2021-04-18 16:03:27
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20170129131956AA7Kt1P