What is the instantaneous slope of y = negative 7/x at x = 3?

Question

tkhunny · Answer

Shall we utilize the 1st Derivative?

anonymous · Answer

tkbunny is right, you need to solve this by first finding the derivative of $$-\frac{ 7 }{ x }$$
and then plug 3 in your new formula

imqwerty · Answer

LOL *tkhunny

anonymous · Answer

eh bunny sounds hotter

imqwerty · Answer

yeah xD

imqwerty · Answer

slope is given by this expression -$$slope=\frac{ dy }{ dx }$$

tkhunny · Answer

It may be an algebra exercise.  I'm still waiting for a hint from the OP.

imqwerty · Answer

@chris215

chris215 · Answer

is the derivative 7x^-2?

imqwerty · Answer

u can write 7/x like this-$$7x^{-1}$$  :)

anonymous · Answer

When possible, you want to get rid of the fraction and that means you want to move x to the numerator.  And how is that done?
Remember that 
$$x = x ^{1}$$
because any number raised to the power of 1 is simply that number, and when using derivatives, you want to make all your x's in exponential formats

Then you can rewrite it like this
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anonymous · Answer

yep

imqwerty · Answer

$$\frac{ 1 }{ a^b }=a^{-b}$$

anonymous · Answer

then you can move the x^-2 to the bottom to make it a positive exponent, plug 3 in the "x" and then that will give you the instantaneous slope

anonymous · Answer

sorry it's actually -7x^-2

anonymous · Answer

because using the exponent rule for derivatives
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