若x属于[0,兀/2],sin(x -兀/6)=6/10,求cosx,

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若x属于[0,兀/2],sin(x -兀/6)=6/10,求cosx,

若x属于[0,兀/2],sin(x -兀/6)=6/10,求cosx,
若x属于[0,兀/2],sin(x -兀/6)=6/10,求cosx,

若x属于[0,兀/2],sin(x -兀/6)=6/10,求cosx,
sin(x -兀/6)=3/5
cosx=cos(x-兀/6+兀/6)=cos(x -兀/6)cos兀/6-sin(x -兀/6)sin兀/6
=4/5*(根号3)/2-3/5*1/2
=(4根号3-3)/10

x属于[0,兀/2], sin(x -兀/6)=6/10=3/5 cos(x -兀/6)=4/5
cosx=cos[(x -兀/6)+兀/6]=cos(x -兀/6)cos兀/6-sin(x -兀/6)sin兀/6
=4/5*√3/2-3/5*1/2
=(4√3-3)/10

cosx=cos(x-pi/6+pi/6)
=cos(x-pi/6)cos(pi/6)-sin(x-pi/6)sin(pi/6)
=(自己继续)