求教三角函数.我只晓得Z=X÷tan(32.1),求已知Y怎么算X和Z.
已知x/z=ln(z/y),求z对x和y的偏导.
三角函数最值问题已知x,y,z为实数,求:f(x,y,z)=[sin(x-y)]^2+[sin(y-z)]^2+[sin
已知x+y-z/z=x-y+z/y=-x+y+z/x,且xyz不等于0,求分式[(x+y)(x+z)(y+z)]/xyz
已知:(x+y-z)/z=(x-y+z)/y+(y+z-x)/x,且xyz≠0,求代数式[(x+y)(y+z)(x+z)
已知3x+7y+z=315和4x+10y+z=420,求x+y+z
X-Y=Z X+Y+Z=80已知Y等于10求X和Z
已知方程组3x+5y+3z=0,3x-5y-8z=0,并且z≠0,求x:z和y:z
已知x,y,z满足x/(y+z)+y/(z+x)+z/(x+y)=1,求代数式x2/(y+z)+y2/(x+z)+z2/
已知实数x,y,z满足x/(y+z)+y/(z+x)+z/(x+y)=1,求x2/(y+z)+y2/(z+x)+z2/(
y+z÷x=Z+X÷y=X+Y÷z,X+Y+Z不等0求X+Y-Z÷X+Y+z值
已知方程组2x-3y-4z=0和x+y+z=0,并且z≠0,求x:y与y:z
已知x,y,z满足{4x-3y-3z=0,x-3y+z=0.(x不等于0,y不等于0,z不等于0)求x/z和y/z的值