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已知sin(x+π/6)=1/4,求sin(5π/6+x)+sin^2(π/3-x)

题目详情
已知sin(x+π/6)=1/4,求sin(5π/6+x)+sin^2(π/3-x)
▼优质解答
答案和解析
sin(5π/6-x)=sin(π-(x+π/6))=sin(x+π/6)=1/4
sin(π/3-x)=sin(5π/6-x-π/2)=-cos(5π/6-x)
sin^2(π/3-x)=cos^2(5π/6-x)=1-(1/4)^2=15/16
sin(5π/6-x)+sin^2(π/3-x)=1/4+15/16=19/16