下列函数在(-∞,+∞)内单调递减的是(  )

下列函数在(-∞,+∞)内单调递减的是(  ) A.y=-x B.y=x2 C.y=-x2 D.y=cosx

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外无期功强近之亲,内无应门五尺之童。茕茕孑立,形影相吊。

外无期功强近之亲,内无应门五尺之童。茕茕孑立,形影相吊。

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判定下列级数的收敛性:

判定下列级数的收敛性:

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According to the passage, how many miles is the earth's diam

According to the passage, how many miles is the earth's diameter?A.2,000. B.4,00

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We feel an object is heavy

We feel an object is heavyA.because weight is a fixed quality in an object. B.be

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