Question: Geometry ....................................

Let triangle ABC and \angle{B}=2\angle{A},\angle{C}=4\angle{A}.
1.Prove that \frac{1}{a}=\frac{1}{b}+\frac{1}{c}
2.Prove thatcos^2A+cos^2B+cos^2C=\frac{5}{4}

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