Solve 5 cos(2?) = 5 cos²(?) – 4 for all solutions 0 ? ? < 2? ? = Give your answers accurate to at least 2 decimal places, as a list separated by commas
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Step 1:** Use the double angle formula to simplify the equation: \[5 \cos(26^\circ) = 5 \cos(\theta)\] \[10 \cos^2(26^\circ) - 5 = 5 \cos^2(\theta) - 4\] \[5 \cos^2(26^\circ) - 1 = \cos^2(\theta)\] ** Show more…
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