Pre-Calc/Trig Unit 3: Analytic Trig and Applications/5.5 Double Angle Identities
Use an identity to write the expression as a single trigonometric function ...
Use an identity to write the expression as a single trigonometric function or as a single number.
2 cos2 22.5° - 1]]>
1.0000000
0.3333333
0
true
true
abc
]]>
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Incorrect. Think of "doubling" 22.5°.]]>
]]>
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Correct]]>
]]>
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Incorrect. Think of "doubling" 22.5°.]]>
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Incorrect. Think of "doubling" 22.5°.]]>