已知二次函数f(x)=ax的平方+x,若X属于【0 1】时有f(x)的绝对值小于等于1恒成立,则实数af(x)=-x满足,对于任意的 属于【0,1】都有f()-f()的绝对值小于等于1恒成立,则a的取值范围

已知二次函数f(x)=ax的平方+x,若X属于【0 1】时有f(x)的绝对值小于等于1恒成立,则实数af(x)=-x满足,对于任意的 属于【0,1】都有f()-f()的绝对值小于等于1恒成立,则a的取值范围
已知二次函数f(x)=ax的平方+x,若X属于【0 1】时有f(x)的绝对值小于等于1恒成立,则实数a
f(x)=-x满足,对于任意的 属于【0,1】都有f()-f()的绝对值小于等于1恒成立,则a的取值范围

已知二次函数f(x)=ax的平方+x,若X属于【0 1】时有f(x)的绝对值小于等于1恒成立,则实数af(x)=-x满足,对于任意的 属于【0,1】都有f()-f()的绝对值小于等于1恒成立,则a的取值范围
若X属于【0 1】时有f(x)的绝对值小于等于1恒成立
即当x∈[0,1]时,-1≤f（x）≤1
即在[0,1]内,这个二次函数的最大值小于1,最小值大于-1
f'（x）=2ax+1=0 解得x=-1/2a
当-1/2a＜0,即a＞0时,
f（0）为最小=0＞-1成立；
f（1）为最大=a+1 因为a＞0,所以1+a＞1,不满足条件 舍掉
当-1/2a＞1,即a＜-2时,
f（0）为最大=0＜1成立；
f（1）为最小=a+1 因为a＜-2,所以a+1＜-1,不满足条件,舍掉
当0≤-1/2a≤1 即-2≤a≤0时
f（-1/2a）为最大=1/4a-1/2a=-1/4a 这里-1/4a≤1,解得-4a≥1,得a≤-1/4
f（0）=0 满足条件
f（1）=a+1 满足a+1＞-1,即a＞-2
综上,a的取值范围为[-2,-1/4]

对函数求导，得f'(x)=2ax+1，
令f'（x）=0，即2ax+1=0 解得x=-1/2a
若-1/2a＜0，即a＞0时，
f（0）=0，属于[-1,1],符合条件；
f（1）=a+1 因为a＞0，所以1+a＞1，不满足条件，所以-1/2a＜0 不成立；
若-1/2a＞1，即a＜-2时，
f（0）=0属于[-1,1],符合条件；
f（1...

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对函数求导，得f'(x)=2ax+1，
令f'（x）=0，即2ax+1=0 解得x=-1/2a
若-1/2a＜0，即a＞0时，
f（0）=0，属于[-1,1],符合条件；
f（1）=a+1 因为a＞0，所以1+a＞1，不满足条件，所以-1/2a＜0 不成立；
若-1/2a＞1，即a＜-2时，
f（0）=0属于[-1,1],符合条件；
f（1）=a+1 因为a＜-2，所以a+1＜-1，不满足条件，所以-1/2a＞1 不成立；
则有 0≤-1/2a≤1 即-2≤a≤0；
当x＞-1/2a时，f'（x）＞0，函数单调递增，当x＜-1/2a时，f'（x）＜0，函数单调递减，
f（0）=0， f（1）=a+1，f（-1/2a）=1/4a-1/2a=-1/4a 都属于[-1,1]
得a的范围为[-2,-1/4]

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1) a＞0时，开口向上，对称轴x=－1/2a＜0，f(x)在【0 1】单调增,f(0)=0,
则f(1)=a＋1≤1，即a≤0，矛盾所以不存在。
2）a＜0时，开口向下，对称轴x=－1/2a＞0，
a）当对称轴x=－1/2a＞1时，即－1/2＜a＜0时，f(x)在【0 1】单调增,f(0)=0,
则f(1)=a＋1≤1，即a≤0，所以－1/2＜a＜0
b）...

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1) a＞0时，开口向上，对称轴x=－1/2a＜0，f(x)在【0 1】单调增,f(0)=0,
则f(1)=a＋1≤1，即a≤0，矛盾所以不存在。
2）a＜0时，开口向下，对称轴x=－1/2a＞0，
a）当对称轴x=－1/2a＞1时，即－1/2＜a＜0时，f(x)在【0 1】单调增,f(0)=0,
则f(1)=a＋1≤1，即a≤0，所以－1/2＜a＜0
b）当对称轴x=－1/2a∈（0，1】时，即a≤－1/2，
所以有f(0)=0∈[-1,1]，f(1)=a＋1∈[-1,1]，f(－1/2a)=－1/4a∈[-1,1]，
即，-2≤a≤0且a≤－1/4，所以-2≤a≤－1/2。
由a）。b）得到-2≤a＜0
综上得到-2≤a＜0

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Money Master Basketball shoes Ugg Boots For females Be able to get Additional info In regard to Dunkle Ugg Boots? Learn Correct
Some sort of high heels are generally elegant that can also turn out...

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Money Master Basketball shoes Ugg Boots For females Be able to get Additional info In regard to Dunkle Ugg Boots? Learn Correct
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