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计算：|﹣1|﹣（﹣2）3﹣+（π﹣cos60°）0．
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函数Cos60°+ψ展开式为
Cos60° Cosψ +Sin60° Sinψ
Cos60° Cosψ -Sin60° Sinψ
Sin60° Cosψ -Cos60° Sinψ
Sin60° Cosψ +Cos60° Sinψ
计算sin30°·cos60°－cos30°·tan60°
计算0.25×-cos60°－2－－10＋tan60°
下列各式中正确的是
sin20
0
+sin30
0
=sin50
0
；
sin60
0
=2sin30
0
；
tan20
0
﹒tan70
0
=1；
cos30
0
＜cos60
0
；
sin245°-cos60°+tan60°·cos230°
计算tan30°cos60°+tan45°cos30°.
计算＋－30－|－|－2-1－cos60°＝____________.
有一直齿锥齿轮副轴交角Σ=60°小齿轮齿数z1=20大齿轮齿数z2=60 试计算两齿轮分锥角的大小
计算2﹣1+•cos60°﹣π+20150.
计算cos60°＝.
1计算:＋π－30－－cos60°
下列各式中正确的是
sin30
0
+cos60
0
=1
sinA=
=30
0
cos60
0
=cos(2×30
0
)=2cos30
0
tan60
0
+cot45
0
=2
计算cos60°﹣2﹣1+﹣π﹣30.
如果水平转弯坡度从60°增大到80°cos60°=0.5cos80°=0.167载荷因数将增加
2
3
4
计算2-1+-cos60°=.
计算|﹣2|+2﹣1﹣cos60°﹣1﹣0.
计算﹣2+π2﹣π0+cos60°+|﹣2|
计算tan30°cos60°+tan45°cos30°.
计算|﹣2|+2﹣1﹣cos60°﹣1﹣0.
函数Cos60°+Cos240°的值为
√ 3
2√ 3
1
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不等式组的解集是．
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对于题目“如图1平面上正方形内有一长为12宽为6的矩形它可以在正方形的内部及边界通过移转即平移或旋转的方式自由地从横放移转到竖放求正方形边长的最小整数n．”甲乙丙作了自认为边长最小的正方形先求出该边长x再取最小整数n． 甲如图2思路是当x为矩形对角线长时就可移转过去结果取n＝13． 乙如图3思路是当x为矩形外接圆直径长时就可移转过去结果取n＝14． 丙如图4思路是当x为矩形的长与宽之和的倍时就可移转过去结果取n＝13． 下列正确的是
如图约定上方相邻两数之和等于这两数下方箭头共同指向的数． 示例即4+3＝7 则1用含x的式子表示m＝ 2当y＝﹣2时n的值为．
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=300 cos600=cos(2×300 )=2cos300 tan600+cot450=2
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