sinθ·cosθ=1/8; 且π/4<θ<π/2 求sinθ-cosθ

cosθ+μsinθ的单调性（0<μ<1,0<θ<90°）cosθ+μsinθ的单调性（0<μ<1,0<θ<90°）cosθ+μsinθ的单调性（0&l

若0<θ<二分之π,且满足方程2cos²θ-sinθ=1.则θ若0<θ<二分之π,且满足方程2cos²θ-sinθ=1.则θ若0<θ<二分之π,

已知sin[(π/4)-x)]=5/13,0<x<π/4.求cos2x/(cosπ/4+已知sin[(π/4)-x)]=5/13,0<x<π/4.求cos2x/[cos(π/4

已知0<A<π/2<B<π,cos(B-π/4)=1/3,sin(A+B)=4/5求cos(a+π/4)的值已知0<A<π/2<B<π,cos(B-π/

已知sin(θ-15°)=3/5,90°<θ<270°,求cos(2θ+15°)的值已知sin(θ-15°)=3/5,90°<θ<270°,求cos(2θ+15°)的值已知si

若sinθ·cosθ=1/8,求sinθ+cosθ?怎样用单位圆确定sinθ和cosθ大若sinθ·cosθ=1/8,求sinθ+cosθ?怎样用单位圆确定sinθ和cosθ谁大谁小?θ属于（π/4，

新手求教matlabfmincon函数的问题等待中.求在0<α<=π/2;0<β<=π/2,θ=0时的最小值,functionf=myfirstfun(x)f=abs(1/((

已知tan(a+π/4)=-1/2,π/2<a<π,求(sin2a-2cos^2a)/√2sin(a-π/4)的值已知tan(a+π/4)=-1/2,π/2<a<π,求(sin

已知tan2x=-2π/2<2x<π求[2cos^2(x/2)-sinx-1]/根号2sin(π/4+x)已知tan2x=-2π/2<2x<π求[2cos^2(x/2)-sin

(已知0<α<π,tanα=-2)求2sin²α-sinαcosα+cos²α求老师帮忙.(已知0<α<π,tanα=-2)求2sin²α-sin

已知π/4<a<b<π/2,且sin(a+b)=4/5,cos(a-b)=12/131、用a+b,a-b表示2a；2、求cos2a,sin2a,tan2a的值.已知π/4<a&

已知sina+cosa=1/5(0<a<π),求tana的值已知sina+cosa=1/5(0<a<π),求tana的值已知sina+cosa=1/5(0<a<π)

sinθcosθ=1/8,θ∈(π/4,π/2),求cosθ-sinθ的值sinθcosθ=1/8,θ∈(π/4,π/2),求cosθ-sinθ的值sinθcosθ=1/8,θ∈(π/4,π/2),求

已知向量m=(Cosθ,Sinθ)和n(根号2-Sinθ,Cosθ),且Im+nl=求Cos(θ/2+π/8)已知向量m=(Cosθ,Sinθ)和n(根号2-Sinθ,Cosθ),且Im+nl=求Co

已知cos(α-β)=-4/5,sin(α+β)=-3/5,π/2<α-β<π,3π/2<α+β<2π,求β的值已知cos(α-β)=-4/5,sin(α+β)=-3/5,π/

已知0<b<π/4,π/4<a<3π/4,cos(π/4-a)=3/5,sin(3π/4+b)=5/13,求sin(a+b)已知0<b<π/4,π/4<a&l

已知tan(θ+π/4)=-2,求cosθ平方+sinθcosθ-1已知tan(θ+π/4)=-2,求cosθ平方+sinθcosθ-1已知tan(θ+π/4)=-2,求cosθ平方+sinθcosθ

已知sin(θ+kπ)=-2cos(θ+kπ)求⑴4sinθ-2cosθ/5cosθ+3sinθ;⑵(1/4)sin平方θ+(2/5)cos平方θ已知sin(θ+kπ)=-2cos(θ+kπ)求⑴4s

2sinθ=cosθ+1,怎么求sin2sinθ=cosθ+1,怎么求sin2sinθ=cosθ+1,怎么求sin用同角三角函数关系式全部展开收起

2sinθ-cosθ=1(sinθ+cosθ+1)/(sinθ-cosθ+1)如题已知2sinθ-cosθ=1求(sinθ+cosθ+1)/(sinθ-cosθ+1)2sinθ-cosθ=1(sinθ