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प्रश्न
Find the value of the following:
sin2 30° – 2 cos3 60° + 3 tan4 45°
उत्तर
sin 30° = `1/2`, cos 60° = `1/2`, tan 45° = 1
sin2 30° – 2 cos3 60° + 3 tan4 45°
= `(1/2)^2 - 2(1/2)^3 + 3(1)^4`
= `(1/4) - 2(1/8) + 3`
= `(1/4) - (1/4) + 3`
= 3
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