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Question
(3 sin2 30° – 4 cos2 60°) is equal to ______.
Options
`5/4`
`-3/4`
`-1/4`
`-9/4`
Solution
(3 sin2 30° – 4 cos2 60°) is equal to `underlinebb(-1/4)`.
Explanation:
`\implies` 3 sin2 30° – 4 cos2 60°
`\implies 3 xx (1/2)^2 - 4 xx (1/2)^2`
`\implies - 1/4`
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