1. ## suppose..

yea i don't even know where to start on this problem...

Suppose and . Find when .

(dx/dt)=?

2. Originally Posted by tbenne3
yea i don't even know where to start on this problem...

Suppose and . Find when .

(dx/dt)=?
$
\frac{d}{dt}\left(xy = 3\right)
$

$
x \cdot \frac{dy}{dt} + y \cdot \frac{dx}{dt} = 0
$

take it from here?

3. Originally Posted by skeeter
$
\frac{d}{dt}\left(xy = 3\right)
$

$
x \cdot \frac{dy}{dt} + y \cdot \frac{dx}{dt} = 0
$

take it from here?
is it -3?

4. $\frac{dx}{dt}=\frac{dx}{dy}\frac{dy}{dt}$

5. Originally Posted by tbenne3
this is not that difficult.

$xy = 3$

if $x = -3$ , then $-3y = 3$ ... $y = -1$

you were given $\frac{dy}{dt} = -3$ ... now use the derivative equation to solve for $\frac{dx}{dt}$

6. Originally Posted by skeeter
this is not that difficult.

$xy = 3$

if $x = -3$ , then $-3y = 3$ ... $y = -1$

you were given $\frac{dy}{dt} = -3$ ... now use the derivative equation to solve for $\frac{dx}{dt}$
sorry just not following.. what is the derivative of dx/dt

7. $
x \cdot \frac{dy}{dt} + y \cdot \frac{dx}{dt} = 0
$

$(-3) \cdot (-3) + (-1) \cdot \frac{dx}{dt} = 0$

solve for the value of $\frac{dx}{dt}$

8. Originally Posted by skeeter
$
x \cdot \frac{dy}{dt} + y \cdot \frac{dx}{dt} = 0
$

$(-3) \cdot (-3) + (-1) \cdot \frac{dx}{dt} = 0$

solve for the value of $\frac{dx}{dt}$
thanks