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Question
find the value of :
3sin2 30° + 2tan2 60° - 5cos2 45°
Solution
3 sin2 30° + 2 tan2 60° – 5 cos2 45°
= `3(1/2)^2 +2(sqrt3)^2 – 5(1/sqrt2)^2`
= `(3)/(4)+6 –(5)/(2)`
= `(3 + 24 – 10)/(4)`
= `4(1)/(4)`
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