The image of a point after a reflection over the line y = –x is (7, –1). find the coordinates of the preimage.

a) (-7, -1)
b) (-7, 1)
c) (-1, 7)
d) (1, -7)

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).