• 2022-06-11
    设\(f\left( {x,y,z} \right) = x{y^2} + y{z^2} + z{x^2}\),则\({f_{yz}}\left( {0,-1,0} \right) = \)( )
    A: 1
    B: 0
    C: -1
    D: 2
  • 举一反三