Q36 of 51 Page 54

Evaluate the following: sin225° + sin265° + √3.(tan5°tan15°tan30°tan75°tan85°)

Formula: -


(i) sin2x + cos2x = 1


(ii) tan(90° – θ) = cotθ


sin225° + sin265° + √3.(tan5°tan15°tan30°tan75°tan85°)




using formula (i) & (ii)


= 1 + 1
= 2


sin225° + sin265° + √3.(tan5°tan15°tan30°tan75°tan85°) = 2


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