Two students join a puzzle solving club and get faster at finishing the puzzles as they get more practice.

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).

Solve the system of equations. y= 2x y= x^2 - 15

Planning for the possibility that your home might get struck by lighting and catch on fire is part of a plan for ?