作业帮2X²-5X-12 7X²-19X-6X²Y²+2XY-8X²+2XY-8Y²
来源：学生作业帮助网 编辑：作业帮 时间：2024/10/05 12:42:54
xA
0ER$! i-&=GHMt
Bcq+mqjf|&9I IhtcIxBeMd5?JC}˜H"1F
㮹~ :_Djcy_
̋'WC$)qM%v*P1r \n h!i:"Mä[n% l46ª/
2X²-5X-12 7X²-19X-6X²Y²+2XY-8X²+2XY-8Y²
2X²-5X-12
7X²-19X-6
X²Y²+2XY-8
X²+2XY-8Y²
2X²-5X-12 7X²-19X-6X²Y²+2XY-8X²+2XY-8Y²
2X²-5X-12 =(2x+3)(x-4) 十字相乘
7X²-19X-6=(7x+2)(x-3) 十字相乘
X²Y²+2XY-8=(xy-2)(xy+4) 十字相乘
X²+2XY-8Y²
=X²+2XY+Y²-9Y²
=(X+Y)²-9Y²
=(X+Y-3Y)(X+Y+3Y)
=(X-2Y)(X+4Y)
2X²-5X-12=（2x+3）（x-4）
7X²-19X-6=（7x+2）（x-3)
X²Y²+2XY-8=(xy-2）（xy+4)
X²+2XY-8Y²=（x-2y)(x+4y)