Questions
Question 1
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State Euler's formula.
Question 2
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State Euler's identity obtained from Euler's formula when \(\theta=\pi\).
Question 3
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Use Euler's formula to write \(e^{-i\theta}\) in terms of sine and cosine.
Question 4
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Evaluate \(e^{i0}\) using Euler's formula.
Question 5
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Evaluate \(e^{i\pi/3}\) in Cartesian form.
Question 6
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Evaluate \(e^{-i\pi/4}\) in Cartesian form.
Question 7
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Derive \(\cos\theta=(e^{i\theta}+e^{-i\theta})/2\).
Question 8
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Derive \(\sin\theta=(e^{i\theta}-e^{-i\theta})/(2i)\).
Question 9
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Use Euler's formula to compute \(e^{i\pi/6}e^{i\pi/3}\).
Question 10
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Use Euler's formula to show that \(|e^{i\theta}|=1\).
Question 11
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Explain how Euler's formula connects complex exponentials to circular motion.
Question 12
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A student writes \(e^{i\theta}=\cos\theta+\sin\theta\). Identify the error.
Question 13
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Use Euler's formula to simplify \(e^{i\theta}+e^{i(\theta+\pi)}\).
Question 14
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Use Euler's formula to express \(2\cos\theta\) as a sum of complex exponentials.
Question 15
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For which real \(\theta\in[0,2\pi)\) is \(e^{i\theta}=i\)?
Question 16
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For which real \(\theta\in[0,2\pi)\) is \(e^{i\theta}\) real?
Question 17
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For which real \(\theta\) does \(e^{i\theta}=e^{-i\theta}\)?
Question 18
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Use Taylor series to justify Euler's formula by grouping real and imaginary terms.
Question 19
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Prove \(e^{i(\theta+2\pi)}=e^{i\theta}\) using Euler's formula.
Question 20
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A learner argues that \(e^{i\pi}=e^i e^\pi\). Explain why this is incorrect and give the correct value.