比较sin(-1)、cos(-1)、tan(-1)的大小 sin1和cos1怎么比较大小，求详解
sin1\uff0ccos1\uff0ctan1\u7684\u5927\u5c0f\u5173\u7cfb\u662f______\u7531\u9898\u610f\uff0c1\uff1e45\u00b0\uff0c\u6240\u4ee5\u5728\u5355\u4f4d\u5706\u4e2d\uff0c\u505a\u51fa\u9510\u89d21\u7684\u6b63\u5207\u7ebf\u3001\u6b63\u5f26\u7ebf\u3001\u4f59\u5f26\u7ebf\uff0c\u53ef\u5f97\u6b63\u5207\u7ebf\u6700\u957f\uff0c\u4f59\u5f26\u7ebf\u6700\u77ed\uff0c\u6240\u4ee5\u6709cos1\uff1csin1\uff1ctan1\uff0c\u6545\u7b54\u6848\u4e3acos1\uff1csin1\uff1ctan1\uff0e
\u901a\u8fc7\u4f5c\u5dee\u6765\u6bd4\u8f83
sin1-cos1=\u221a2sin(1-\u03c0/4)
\u22351-\u03c0/4\u2208(0,\u03c0),\u2234\u221a2sin(1-\u03c0/4)>0
\u2234sin1>cos1
\u8fd8\u53ef\u4ee5\u7528\u4f5c\u5546\u6765\u6bd4\u8f83
sin1>0,cos1>0
sin1/cos1=tan1>tan(\u03c0/4)=1
\u2234sin1>cos1
cos(-1)>sin(-1)>tan(-1)
cos1=sin(π/2-1)
因为0<π/2-1<1<π/2,所以cos1=sin(π/2-1)<sin1
又因为sin1<1<tan1
所以cos1<sin1<tan1
∵cos1＝cos(-1)
sin1＝-sin(-1)
tan1＝-tan(-1)
∴tan(-1)＜sin(-1)＜cos(-1)
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