二次根式 计算和化简求值问题
来源:学生作业帮 编辑:搜搜做题作业网作业帮 分类:数学作业 时间:2024/07/17 14:39:14
二次根式 计算和化简求值问题
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1、2a(a+b)-(a+b)²
=2a²+2ab-a²-2ab-b²
=a²-b²
=(√2012)²-(√2013)²
=2012-2013
=-1
2、(√x+12)²-(√x+2)²
=(x+12)-(x+2)
=x+12-x-2
=10
=2a²+2ab-a²-2ab-b²
=a²-b²
=(√2012)²-(√2013)²
=2012-2013
=-1
2、(√x+12)²-(√x+2)²
=(x+12)-(x+2)
=x+12-x-2
=10