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Question
Choose the correct alternative:
If cos 28° + sin 28° = k3, then cos 17° is equal to
Options
`"k"^3/sqrt(2)`
`- "k"^3/sqrt(2)`
` +- "k"^3/sqrt(2)`
`- "k"^3/sqrt(3)`
Solution
`"k"^3/sqrt(2)`
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