
Differentiate both sides, treating
as a function of
. Let's take it one term at a time.
Power, product and chain rules:



Product and chain rules:




Product and chain rules:




The derivative of 0 is, of course, 0. So we have, upon differentiating everything,

Isolate the derivative, and solve for it:


(See comment below; all the 6s should be 2s)
We can simplify this a bit by multiplying the numerator and denominator by
to get rid of that fraction in the denominator.

So x=-2 after ndjsbdbbegshwoehev
Answer:
19 mm
Step-by-step explanation:
A penny is not that large, and you can fit multiple pennies in the palm of your hand. This means that the only reasonable measurement is 19 mm, (& 8 cm, but that is only if you have really large hands). Therefore, (A) is your choice.
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