求值sin^2A+cos^2(A+30°)+sinAcos(A+30°)
求值sin^2A+cos^2(A+30°)+sinAcos(A+30°)
高一数学已知sinacos(a-b)+sin(b-a)sin(π/2-a)=-4/5,求cos(π/2+b)的值
1已知sina+cosa=-7/5 求tana-cota2已知sin(a-3π)=2cos(a-4π) 求sinacos
先化简,再求值:(sin a-cos a)÷(sin a+cos a),其中tan a=2
sin^a+cos^(π/6+a)+1/2sin(2a+π/6)求值
已知tana=3 求根号下(sin^4a-3sinacos^3a+cos^4a)
已知cos(a/2)-sin(a/2)=1/5,求值tan a
求值sin^2a+cos^2a(π/6+a)+1/2sin(2a+6/π)
已知cos(a+b)=0,求值:sin(π+2a+b)-cos(-π/2+2a+3b)
2sinasinβ+cos(a+β)分之sin(a+β)-2sinacisβ 化简求值
求值4sin^2a-3sinacosa-5cos^2a
已知(tan a-3)(sin a+cos a+3)=0,求值:2/3sin²a+1/4cos²a