Question

cos 57° sin 33° + sin² 123°
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Answer 1

cos57°sin33°+sin²123°=cos57°×sin(90°-57°)×sin²123=cos57°×cos57°+sin²123°=cos²57°+sin²123°=cos²57+sin²(180°-57°)=cos²57°+sin²57°=1