4b-1=-13
what is the freaking answer to this stoopid prollem
plz answer my dumb question

Ineed asap.i cant understand this question i need someone to me right away

Find the gradient of f(x,y,z)equals=left parenthesis x squared plus y squared plus z squared right parenthesis superscript negative 1 divided by 2 baseline plus ln left parenthesis x right parenthesis x2+y2+z2−1/2+ln(xyz) at the point left parenthesis negative 2 comma 1 comma negative 2 right parenthesis(−2,1,−2).

What is the value of f(x) = 2.2 for f(-2)?