设角a=-35π/6,2sin(兀+a)cos(兀-a)-cos(兀+a)/1+sin^2a+sin(兀-a)-cos^
来源:学生作业帮 编辑:作业帮 分类:数学作业 时间:2024/05/21 11:30:25
设角a=-35π/6,2sin(兀+a)cos(兀-a)-cos(兀+a)/1+sin^2a+sin(兀-a)-cos^2(兀+a)值等于
[2sin(兀+a)cos(兀-a)-cos(兀+a)]/[1+sin^2a+sin(兀-a)-cos^2(兀+a)]利用诱导公式对原式化简=[2sinacosa+cosa]/[1+sin^2a+sina-cos^2a]利用1=sin^2a+cos^2a公式对上式化简= [2sinacosa+cosa]/[2sin^2a+sina]=cosa/sina=cota a=-35π/6 代入cot(-35π/6 )=cot(-6π+π/6)=cot(π/6)=根号3
已知a(-0,兀且2SIN A-SIN ACOS A-3COS A=0求SIN(+兀/4)/SIN 2A+COS 2A+
已知a属于(0,π/2),且2sin^2 a-sin a cos a-3cos^2 a=0,求SIN(a+兀/4)/SI
证明Cos^A-Sin^A=1-2Sin^A=2Cos^A-1=cos^a-sin^a
化简sin(兀+a)cos(3/2兀+a)+sin(兀/2+a)cos(兀+a)=
化简(1-sin^6 a-cos^6 a)/(cos^2 a-cos^4 a)==
化简:sin(-a)cos(2π+a)sin(-a-π)
化简[cos(a-π)/sin(π-a)]sin(a-π/2)cos(π/2+a)=
化简Sin A + Sin 2A / 1+cos A +
tan a/2=sin/1+cos a=1-cos a/sin a
求证:tan a/2=(1-cos)/sin a=sin a/(cos a+1)
已知 sin a-cos a=1/2,则 sin^3 a-cos^3 a
证明sin(4A)sin(2A)(1-cos(2A)) cos(4A)cos(2A)(1 cos(2A))=cos(2A