A smokestack deposits soot on the ground with concentration inversely proportional to the square of the distance from the stack. With two smokestacks 20 miles apart, the concentration of the combined deposits on the line joining them, at a distancexfrom one stack, is given by the following equation wherek1 andk2 are positive constants which depend on the quantity of smoke each stack is emitting.

Ifk1 = 27k2, find the point on the line joining the stacks where the concentration of the deposit is a minimum.

x=

can someone please help me out with this one...much thanks

mathaction