在实数范围内分解因式(1) 2x²+2x-1 (2)x²-2xy-y²
来源:学生作业帮助网 编辑:作业帮 时间:2024/11/30 07:49:15
x){:guM-OZvXOa~OQQP(
5ԭmm~
M܉]XH&76757Dk4vebz@ڏ:f!<](D|@цhѭ SJMS´/.H̳
c71! r
在实数范围内分解因式(1) 2x²+2x-1 (2)x²-2xy-y²
在实数范围内分解因式(1) 2x²+2x-1 (2)x²-2xy-y²
在实数范围内分解因式(1) 2x²+2x-1 (2)x²-2xy-y²
(1) 2x²+2x-1
=2(x²+x-1/2)
=2(x²+x+1/4-3/4)
=2[(x+1/2)²-3/4]
=2(x+1/2+√3/2)(x+1/2-√3/2)
(2)x²-2xy-y²
=(x²-2xy+y²)-2y²
=(x-y)²-2y²
=(x-y+√2y)(x-y-√2y)
1.2x²+2x-1
=2(x²+x-1/2)
=2(x²+x+1/4-3/4)
=2[(x+1/2)²-3/4]
=2(x+1/2+√3/2)(x+1/2-√3/2)
(2)x²-2xy-y²
=(x²-2xy+y²)-2y²
=(x-y)²-2y²
=(x-y+√2y)(x-y-√2y)