计算:cos225°+sin(-7派/3)+cos(-2040°)+sin(-16派/3)

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计算:cos225°+sin(-7派/3)+cos(-2040°)+sin(-16派/3)

计算:cos225°+sin(-7派/3)+cos(-2040°)+sin(-16派/3)
计算:cos225°+sin(-7派/3)+cos(-2040°)+sin(-16派/3)

计算:cos225°+sin(-7派/3)+cos(-2040°)+sin(-16派/3)


cos255°+sin(-7π/3)+cos(-2040°)+sin(-16π/3)
=cos(180°+45°)+sin(-2π-π/3)+cos(-2160°+120°)+sin(-6π+2π/3)
=-cos45°-sin(π/3)+cos120°+sin(2π/3)
=-√2/2-√3/2-1/2+√3/2
=-√2/2-1/2
=-(√2+1)/2