倒数、绝对值.相反数.已知ab互为相反数,cd互为倒数,x的绝对值等于5,求X²-﹙a+b+cd﹚X+﹙a+b﹚²º¹¹+﹙-cd﹚²º¹²的值.
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![倒数、绝对值.相反数.已知ab互为相反数,cd互为倒数,x的绝对值等于5,求X²-﹙a+b+cd﹚X+﹙a+b﹚²º¹¹+﹙-cd﹚²º¹²的值.](/uploads/image/z/5372797-13-7.jpg?t=%E5%80%92%E6%95%B0%E3%80%81%E7%BB%9D%E5%AF%B9%E5%80%BC.%E7%9B%B8%E5%8F%8D%E6%95%B0.%E5%B7%B2%E7%9F%A5ab%E4%BA%92%E4%B8%BA%E7%9B%B8%E5%8F%8D%E6%95%B0%2Ccd%E4%BA%92%E4%B8%BA%E5%80%92%E6%95%B0%2Cx%E7%9A%84%E7%BB%9D%E5%AF%B9%E5%80%BC%E7%AD%89%E4%BA%8E5%2C%E6%B1%82X%26%23178%3B%EF%BC%8D%EF%B9%99a%2Bb%2Bcd%EF%B9%9AX%2B%EF%B9%99a%2Bb%EF%B9%9A%26%23178%3B%26%23186%3B%26%23185%3B%26%23185%3B%2B%EF%B9%99-cd%EF%B9%9A%26%23178%3B%26%23186%3B%26%23185%3B%26%23178%3B%E7%9A%84%E5%80%BC.)
倒数、绝对值.相反数.已知ab互为相反数,cd互为倒数,x的绝对值等于5,求X²-﹙a+b+cd﹚X+﹙a+b﹚²º¹¹+﹙-cd﹚²º¹²的值.
倒数、绝对值.相反数.
已知ab互为相反数,cd互为倒数,x的绝对值等于5,求X²-﹙a+b+cd﹚X+﹙a+b﹚²º¹¹+﹙-cd﹚²º¹²的值.
倒数、绝对值.相反数.已知ab互为相反数,cd互为倒数,x的绝对值等于5,求X²-﹙a+b+cd﹚X+﹙a+b﹚²º¹¹+﹙-cd﹚²º¹²的值.
ab互为相反数,所以b=(-a)
因为cd互为倒数,所以d=(1/c)
所以x^2-(a+b+cd)x+(a+b)^2011+(-cd)^2012
=25-[a-a+c(1/c)]x+(a-a)^2011+[-c(1/c)]^2012
=25-1x+1
=26-x
因为x的绝对值等于5
所以答案为26-5=21或26+5=31
26±5
21 31
因为ab互为相反数所以a+b=0 因为cd互为倒数所以c*d(即cd)=1 -cd=-1
因为x的绝对值等于5所以x=±5
x²=25
x²-﹙a+b+cd﹚X+﹙a+b﹚²º¹¹+﹙-cd﹚²º¹²
=25-(0+1)x+0²º...
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因为ab互为相反数所以a+b=0 因为cd互为倒数所以c*d(即cd)=1 -cd=-1
因为x的绝对值等于5所以x=±5
x²=25
x²-﹙a+b+cd﹚X+﹙a+b﹚²º¹¹+﹙-cd﹚²º¹²
=25-(0+1)x+0²º¹¹+(-1)²º¹²
=25-x+1
=26-x
x的绝对值等于5所以x=±5
26-x=21或31
收起
你好,过程如下
原式子=x^2-(0+1)x+0+(-1)^2012
=|x|^2-x+1
=25-x+1
=26-x
因为|x|=5
所以x=正负5
所以最后结果=21或者31