题干

定义:如果函数y=f(x)在定义域内给定区间[a,b]上存在x0(a<x0<b),满足f(x0)= −−
f
(
b
)
f
(
a
)
b
a
,则称函数y=f(x)是[a,b]上的“平均值函数”,x0是它的一个均值点.例如y=|x|是[﹣2,2]上的平均值函数,0就是它的均值点.若函数f(x)=x2﹣mx﹣1是[﹣1,1]上的“平均值函数”,则实数m的取值范围是____.
上一题 下一题 0.0难度 选择题 更新时间:2020-03-24 08:19:03

答案(点此获取答案解析)

(0,2)

同类题1

阅读理解

    No rows of desks in this classroom, and no teacher lecturing at the front. In fact, that's something Barrie teacher Liz Collett rarely does. Instead, she's on the move, talking to students about their work, from the small group sitting on the floor playing games to others nearby figuring out a math problem.

    The children in this class do not take a spelling test all year-in fact, the school avoids all pencil-and-paper tests-nor do they get assigned homework. Instead, their teacher gives them immediate feedback(反馈)on their work throughout the day.

    Welcome to the school of the 21st century, a place where teachers and students cooperate all the time. Such advanced classrooms are trying things, which some might consider as coddling kids-letting students give a voice-recorded essay instead of a written one or even allowing teens to design their own courses.

    Though some people blame(谴责)schools for dumbing things down(降低教育标准), others will say such changes are actually based on the newest research on how to attract today's youth and increase not only their interests, but also their achievements. Many of today's school are not holding kid's interests. And if they Ye not interested, they're not learning-and isn't that the point?

“Students today say they want their education to be useful and valuable, and don't want it to be simply repeating the facts. That's the kind of learning that be happening for many kids,” says Penny Milton, a researcher. “What we could argue is that to become good learners, they need to become thinkers.”

    Jan Olson, anther researcher, says schools have been operating the same way since the Industrial Revolution. But the digital age is bringing an education revolution. While using technology is a part of it, what's important for students is being able to use information and understand it, not just remembering it.

    Today's learner needs fewer traditional tests and more “effective” feedback, ongoing discussion with a teacher, which studies have found is the number one factor in improving achievement.