A to Z Exams

If f(x,y,z)=√(yz)+ √(zx)+ √(xy) then xfx+yfy+zfz=

If au+b=a2x+y then uxuy=

If u=(y+sin x)3+(y-sin x)2,then uxx=

If u=(ax+by)2-(x2+y2) and a2+b2=1 then uxx+uyy=

If V=πr2h then rVr+2hVh=

If u=x2+y2+z2,x=et,y=et sin t,z=et cos t then du/dt=

If u3(1+a3)=8(x+ay+b)3 then u3x+u3y=

If f(x,y)=xy+(1/x)+(1/y) then fxx?fyy-fxy2 at (1,1) is

If r2=(x-a)2+(y-b)2 then rxx+ryy=

If f(x,y)=x2Tan-1(y/x)-y2 Tan-1(x/y),x≠0,y≠0 then fxy=

If V is the volume of a rectangular box with edges x,y,z then Vxyz=

If f=x2yz+y2zx+z2xy then fxyz=

If z(x,y) is the implicit function defined by x3+y3+z3=3xyz then xzx+yzy=

If u=3(lx+my+nz)2-(x2+y2+z2) and l2+m2+n2=1 then uxx+uyy+uzz=

If Z=1n(1+xr+yr) then Zxy=

If u=(x-y) (y-z) (z-x) then ux+uy+uz=