Error Analysis A student solved the equation 2cos θ = √2 for 0 ≤ θ < 2π and got θ = (π/4). What was her error?

Analyzing functions
asked 2021-03-09

Error Analysis A student solved the equation \(2\cos\theta=\sqrt{2}\ for\ 0\leq\theta<2\pi\) and got \(\theta=(\pi/4)\). What was her error?

Expert Answers (1)


\(\cos\theta=(\frac{\sqrt2}{2})\to\theta=\pi/4\ and\ \theta=\frac{7\pi}{4}\)

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