SOLUTION: Use a Double- or Half-Angle Formula to solve the equation in the interval [0, 2π). (Enter your answers as a comma-separated list. Round your answers to three decimal places wh

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Question 888190: Use a Double- or Half-Angle Formula to solve the equation in the interval [0, 2π). (Enter your answers as a comma-separated list. Round your answers to three decimal places where appropriate.)
−sin 2θ − cos 4θ = 0
Answer by lwsshak3(11628) About Me  (Show Source):
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Use a Double- or Half-Angle Formula to solve the equation in the interval [0, 2π). (Enter your answers as a comma-separated list. Round your answers to three decimal places where appropriate.)
−sin 2θ − cos 4θ = 0
***
-sin%282theta%29-cos%284theta%29=0
-sin%282theta%29-%281-2sin%5E2%282theta%29%29=0
-sin%282theta%29-1%2B2sin%5E2%282theta%29=0
2sin%5E2%282theta%29-sin%282theta%29-1=0
%282sin%282theta%29%2B1%29%28sin%282theta%29-1%29=0
..
2sin%282theta%29%2B1=0
sin%282theta%29=-1%2F2
2theta=7π/6, 11π/6
theta=7π/12, 11π/12
or
sin%282theta%29-1=0
sin%282theta%29=1
2theta=pi%2F2
theta=pi%2F4