Questions
Question 1
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State the integration by parts formula.
Question 2
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For \(\int x e^x\,dx\), a useful choice is \(u=x\). What are \(du\), \(dv\), and \(v\)?
Question 3
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In the LIATE guideline, which is normally chosen first: algebraic or exponential?
Question 4
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For \(\int x\cos x\,dx\), choose \(u\) and \(dv\) using LIATE.
Question 5
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Evaluate \(\int x e^x\,dx\).
Question 6
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Evaluate \(\int x\cos x\,dx\).
Question 7
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Evaluate \(\int \ln x\,dx\) for \(x>0\).
Question 8
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Evaluate \(\int x\sin x\,dx\).
Question 9
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Evaluate \(\int x^2 e^x\,dx\).
Question 10
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Evaluate \(\int x^2\cos x\,dx\).
Question 11
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Evaluate \(\int_0^1 x e^x\,dx\).
Question 12
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Verify by differentiating that \(x\sin x+\cos x+C\) is an antiderivative of \(x\cos x\).
Question 13
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Evaluate \(\int x\ln x\,dx\) for \(x>0\).
Question 14
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Evaluate \(\int e^x\sin x\,dx\).
Question 15
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Find \(a\) if \(\int x e^{ax}\,dx=e^{ax}\left(\frac{x}{a}-\frac{1}{a^2}\right)+C\) and the integrand is \(xe^{3x}\).
Question 16
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For which polynomial degree is the tabular method especially efficient in \(\int p(x)e^x\,dx\), and why?
Question 17
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Evaluate \(\int x^3 e^x\,dx\) using repeated integration by parts or the tabular pattern.
Question 18
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A student evaluating \(\int x\cos x\,dx\) writes \(x\sin x-\int\sin x\,dx=x\sin x-\cos x+C\). Find and correct the sign error.
Question 19
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Explain why choosing \(u=e^x\) and \(dv=x\,dx\) is inefficient for \(\int xe^x\,dx\), even though it is not illegal.
Question 20
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Derive the integration by parts formula from the product rule.