In triangle $ABC$,
\[2a^2 + 4b^2 + c^2 = 4ab + 2ac.\]Compute the numerical value of $\cos B.$
Question:
In triangle $ABC$,
\[2a^2 + 4b^2 + c^2 = 4ab + 2ac.\]Compute the numerical value of $\cos B.$
Answer:
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\frac{7}{8}
In triangle $ABC$,
\[2a^2 + 4b^2 + c^2 = 4ab + 2ac.\]Compute the numerical value of $\cos B.$
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