Chapter 4: Problem 60
Show that the function \(T(x)=60 D(60+x)^{-1}\) gives the time in minutes required to drive \(D\) miles at \(60+x\) miles per hour.
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Chapter 4: Problem 60
Show that the function \(T(x)=60 D(60+x)^{-1}\) gives the time in minutes required to drive \(D\) miles at \(60+x\) miles per hour.
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Properties of cubics Consider the general cubic polynomial \(f(x)=x^{3}+a x^{2}+b x+c,\) where \(a, b,\) and \(c\) are real numbers. a. Prove that \(f\) has exactly one local maximum and one local minimum provided that \(a^{2}>3 b\) b. Prove that \(f\) has no extreme values if \(a^{2}<3 b\)
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