The arrangement of 8 coins produces a square, with 3 coins per side and no coins in the centre of the square, you can move 4 of the coins to give a square with 4 coins per side. how do you move the coins? (think outside the box)

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).

Simplify a7/a4 a) 1/a3 b)-a/a2 c)a4/a3 d)a3

Complex numbers multiply √-4 * √-25 and show all intermediate steps. alternative notation is sqrt(-4) * sqrt(-25).