1/sin(x)+4/cos(x)=7*sin(x)cos(x) x为0到180度闭区间 求x

求证（cos^2 x-sin^2 x)(cos^4 x+sin^4 x)+1/4 sin 2x sin 4x=cos 2x 急,matlab解非线性方程组用什么函数呢 方程如下所示：(cos(x(1))*cos(x(3))-sin(x(1))*cos(x(2))*sin(x(3)))*(194-x(4))*x(7)+(cos(x(1))*sin(x(3))+sin(x(1))*cos(x(2))*cos(x(3)))*(145-x(5))*x(7)+sin(x(1))*sin(x(2))*x(6)*x(7)-1=0;(-sin(x(1 证明一个sin&cos的等式证明 1+sin^2(x)+sin^4(x)+sin^6(x)=[1-sin^8(x)]/[cos^2(x)] 1/sin(x)+4/cos(x)=7*sin(x)cos(x) x为0到180度闭区间 求x 求证(3-sin^4 x-cos^4 x)/2cos^2 x=1+tan^2 x+sin^2 x (1+cos x-sin x)/(1-sin x-cos x)+(1-cos x-sin x)/(1-sin x+cos x)=? cos x/sin x+sin x/(1+cos x) 化简. f(x)=(6sin^4x-7sin^2x+2)/(sin^2x-cos^2x) 求证:(sin 2x /(1-cos 2x) )·(sin x /(1+sin x))=tan (π/4-x/2). sin（sin（sin（sin（x）=cos（cos（cos（cos（x）,X等于多少? cos x /sin x= 求证（cos^2x-sin^2x)(cos^4x+sin^4x）+1/4sin2xsin4x=cos2x (1-cos^4X-sin^4x)∕(1-cos^6x-sin^6x)=化简(急) 求证：1-cos^4x-sin^4x/1-cos^6x-sin^6x=2/3 证明1-sin^6x-cos^2x/1-sin^4x-cos^4x=3/2 一道三角函数证明题sin^4 X+cos^4 X=1-2sin^2 X cos^2 X 若sinx+sin^2x=1,则cos^2x+cos^4x=? 求函数y=7-4sin(x)cos(x)+4cos^2(x)-4cos^4(x)值