> 其他 >
已知x的平方减5x减2011等于0,求x减2的和分之x减2的差的立方减x减1的差的平方加1的值.
人气:176 ℃ 时间:2019-08-17 14:21:34
解答
x²-5x-2011=0,x²-5x=2011
[(x-2)³-(x-1)²+1]/(x-2)?
=[(x-2)³+1-(x-1)²]/(x-2)
=[(x-2)³+(1+x-1)(1-x+1)]/(x-2)
=[(x-2)³+x(2-x)]/(x-2)
=[(x-2)³-x(x-2)]/(x-2)
=(x-2)²-x
=x²-4x+4-x
=x²-5x+4
=2011+4
=2015
推荐
猜你喜欢
© 2024 79432.Com All Rights Reserved.
电脑版|手机版