Questions
Question 1
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State the quotient rule for \(\frac{f(x)}{g(x)}\).
Question 2
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What condition must hold before differentiating \(f(x)/g(x)\) at a point?
Question 3
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Differentiate \(\frac{x}{\sin x}\).
Question 4
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Differentiate \(\frac{e^x}{x}\).
Question 5
**
Differentiate \(\frac{x^2}{x+1}\).
Question 6
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Differentiate \(\frac{\sin x}{x}\).
Question 7
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Differentiate \(\frac{x^3+1}{x^2}\) using the quotient rule.
Question 8
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Differentiate \(\frac{\ln x}{x}\) for \(x>0\).
Question 9
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Find \(f'(1)\) for \(f(x)=\frac{x^2+1}{x+2}\).
Question 10
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Differentiate \(\frac{x^2-1}{x-1}\) for \(x\ne1\), and compare with simplifying first.
Question 11
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Differentiate \(\frac{x\cos x}{x+1}\).
Question 12
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Explain the sign order in the quotient rule using \((f/g)'\).
Question 13
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Differentiate \(\frac{x^2\sin x}{e^x}\).
Question 14
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Differentiate \(\frac{x^2+1}{\sin x}\).
Question 15
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Find \(a\) if \(f(x)=\frac{x+a}{x+1}\) has \(f'(0)=3\).
Question 16
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Find all \(x\ne0\) where \(f(x)=\frac{x^2+1}{x}\) has horizontal tangent.
Question 17
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Find \(k\) if \(f(x)=\frac{kx}{x+2}\) has \(f'(2)=1\).
Question 18
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A student differentiates \(\frac{x^2}{x+1}\) as \(\frac{2x}{1}\). Diagnose the error.
Question 19
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Show how the quotient rule follows from writing \(f/g=f\cdot g^{-1}\).
Question 20
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Explain why the derivative of \(\frac{x^2-1}{x-1}\) at \(x=1\) does not exist even though the simplified derivative is \(1\).