(sin230° + 4 cot245° — sec260°)(cosec245° sec230°)

sin 30° = 1/2 sin2 30° = 1/4

cos 45° = 1/√2 = sin 45°


cot 45° = 1 cot2 45° = 1


cos 60° = 1/2 sec 60° = 2 sec2 60° = 4


cos 30° = √3/2 sec 30° = 2/√3 sec2 30° = 4/3


cosec 45° = 1/sin 45° = √2 cosec2 45° = 2


(sin230° + 4 cot245° — sec260°)(cosec245° sec230°)


= ((1/4) + 4(1) – 4) × (2)(4/3)


= (1/4) × (8/3)


= 8/12


= 2/3


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