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Question
Evaluate the following:
2tan2 45° + cos2 30° − sin2 60°
Solution
2tan2 45° + cos2 30° − sin2 60°
= `2(1)^2 + ((sqrt3)/2)^2 - ((sqrt3)/2)^2`
= `2(1)^2 + (sqrt3/2)^2 - ((sqrt3)/2)^2`
= `2+3/4 - 3/4`
= 2
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