已知(a^2)sinθ+acosθ-1=0,(b^2)sinθ+bcosθ-1=0,(θ为变量且a不等于b)求1.点(a,b)所在曲线的方程.2.点(a,a^2),(b,b^2)确定的直线方程.

已知sin a+cos a= -1/5 求1）sin acos a 2）sin a-cos a 已知tana=-1/3,计算：1/2sin acos a+cos²a 已知cos2a=（1/4),求cos^4a+sin^4+sin^2acos^2a的值 已知sin acos b=1,则sin(a-b)= 求证1+sin a+cos a+2sin acos a/1+sin a+cos a=sin a+cos a 已知A(a,a^2)、B(b,b^2)(a≠b)两点的坐标,满足a^2sinθ+acosθ=1,b^2sinθ+bcosθ=1a^2sinθ+acosθ-1=0,b^2sinθ+bcosθ-1=0a=(-cosθ+√(cos^2θ+4sinθ)/(2sinθ)b=(-cosθ-√(cos^2θ+4sinθ)/(2sinθ)a+b=-cotθ.ab=-/sinθ/设直线Y=KX+C,坐标(a 已知a^2+b^2=1 求证:|acos θ +bsinθ |≤ 1 已知(sin A)^2+(sin B)^2+（sin C)^2=1,且A,B,C均为锐角,求cos Acos Bcos C的最大值 求证sin^4a+cos^4a=1-2sin^2acos^2a sin^4a-sin^2acos^2a+cos^2a=1 求证(1-sin^2Acos^2A)(cos2A)=cos^6A-sin^6A 求证sin^6A+cos^6A=1-3sin^2Acos^A 已知:sin^2A/sin^2B+cos^2Acos^2C=1,求证:tan^2Acot^2B=sin^2C 已知sin ^2 2a+sin 2acos 2a-cos 2a=1,a∈(0,2/π)求tan a 已知sin acos b=1,则cos(a+b)=急 已知tan a =-4,求下列各式的值 (1)sin^2 a (2)3sin acos a (3)cos^2 a-sin^2 a (4)4sin a已知tan a =-4,求下列各式的值 (1)sin^2 a (2)3sin acos a (3)cos^2 a-sin^2 a (4) (4sin a-2cos a)/(5cos a+3sin a) a为任意角 已知tan a =-4,求下列各式的值 (1)sin^2 a (2)3sin acos a (3)cos^2 a-sin^2 a (4)4sin a已知tan a =-4,求下列各式的值 (1)sin^2 a (2)3sin acos a (3)cos^2 a-sin^2 a (4) (4sin a-2cos a)/(5cos a+3sin a) a为任意角 已知a^2+b^2=1,求证|aCOS&+bSIN&|