Calculus Problem

[iwannatopcollege]

<p>Hey guys, I am having alot of trouble with this problem. Can you guys help? THanks!</p>

<p>Suppose that the edge lengths x,y,z of a closed rectangular box are changing at the following rates: dx/dt= 2ft/sec, dy/dt = -5ft/sec, dz/dt= 0 ft/sec. FInd the rates at which the box's volume, surface area and diagnoal lenth s = rad ((x^2)+(y^2)+(z^2)) are changing at the instant when x = 7 ft, y = 4 ft and z = 9 ft.</p>

[conker]

<p>This problem is just like any other related rates problem. Or are you having trouble taking a derivative of three variables? To take the derivative of xyz, imagine it as a product of x<em>(yz). You'll have to do the product rule twice (once for x</em>(yz) and once for yz).</p>