penglu7520
幼苗
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sin(-879°)=-sin879°=-sin(2*360°+159°)=-sin(159°)=-sin(180°-21°)=-sin21° ;
tan(-33π/8)=-tan(4π+π/8)=-tan(π/8)=-tan22.5°=-0.4142;
cos(-13π/10)=cos(13π/10)=cos(π+3π/10)=-cos(3π/10)=-cos54°=-0.5878.
比较结果:sin(-879°)>tan(-33π/8)>cos(-13π/10).
1年前
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