神马作文网求值：⑴sin(-19π/3)*cos(19π/6)
来源：学生作业帮 编辑：神马作文网作业帮 分类：数学作业 时间：2024/11/10 19:40:38
求值：⑴sin(-19π/3)*cos(19π/6)
⑵cos(-585°)/[sin(-330°)+tan495°]
已知log2sina=-1且a∈[0,2π）,求a的值
⑵cos(-585°)/[sin(-330°)+tan495°]
已知log2sina=-1且a∈[0,2π）,求a的值
sin(-19π/3)*cos(19π/6)
=-sin(19π/3)*cos(19π/6)
=-sin(6π+π/3)*cos(3π+π/6)
=-sin(π/3)*(-cosπ/6)
=√3/2*√3/2
=3/4
cos(-585°)/[sin(-330°)+tan495°]
=cos(-585°+720°)/[sin(-330°+360°)+tan(495°-540°)]
=cos(135°)/[sin(30°)+(tan-45°)]
=-cos(135°-180°)/[sin(30°)-(tan45°)]
=-√2/2*/[1/2-1]
=√2
log2sina=-1
sina=2^(-1)=1/2
又a∈[0,2π）
a=π/6 或 5π/6
=-sin(19π/3)*cos(19π/6)
=-sin(6π+π/3)*cos(3π+π/6)
=-sin(π/3)*(-cosπ/6)
=√3/2*√3/2
=3/4
cos(-585°)/[sin(-330°)+tan495°]
=cos(-585°+720°)/[sin(-330°+360°)+tan(495°-540°)]
=cos(135°)/[sin(30°)+(tan-45°)]
=-cos(135°-180°)/[sin(30°)-(tan45°)]
=-√2/2*/[1/2-1]
=√2
log2sina=-1
sina=2^(-1)=1/2
又a∈[0,2π）
a=π/6 或 5π/6
求值：⑴sin(-19π/3)*cos(19π/6)
求值：sin(-3分之19π）+cos(-6分之25π）=?
求值：sin(π/4)cos(19π/6)tan(21π/4)急!
化简求值sin(-20/3π)cos(43/6π)+sin(35/6π)cos-(17/3π)
求值：sin(π/12)+cos(π/12)
1.已知tan2分之α=2,求值:⑴ tan(α+4分之π)；⑵ （6sinα+cosα）/（3sinα-2cosα）
求值sin25π/6+cos25π/3+tan(-25π/4)+sin(-7π/3)×cos(-13π/6)-sin(-
sin^a+cos^(π/6+a)+1/2sin(2a+π/6)求值
化简求值:sin(π/4-3x)*cos(π/3-3x)-cos(π/6+3x)*sin(π/4+3x)
求值：sin（π／4+3x）cos（3／π-3x）+cos（π／6+3x）cos（π／4+3x）
求值：1.cos(-14π/3) 2.tan（35π/6） 3.sin（-25π/6）
8sin(π/32)cos(π/32)cos(π/16)cos(π/8),求值