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JMullis
17th June 2009 - 01:54 AM
The problem is as follows
Government economists of a developing country determine dthat the purchase of imported perfune is related to a proposed "luxury tax" by the formula

n(x) = sqare root of 12,0000-40x-0.02x^2

where n(x) measures the percentage of normal consumption of perfume when a "luxury" of x% is imposed on it, Find the rate of change of n(x) for tax of 20%; 100% and 150%. Round the answers to two decimal places.

The given answers are -.19,-.25,-.31.

I don't even know where to start.

I presume that the first step is to state the formula in exponential terms and then to find the derivative to arrive at

-2(-0.02x^-1) -40

What do I do next?

Any help is appreciated.


magpies
17th June 2009 - 02:00 AM
Get all the x to one side for starters.
Grasshopper
17th June 2009 - 11:54 PM
QUOTE (JMullis+Jun 17 2009, 01:54 AM)
The problem is as follows
Government economists of a developing country determine dthat the purchase of imported perfune is related to a proposed "luxury tax" by the formula

n(x) = sqare root of 12,0000-40x-0.02x^2

where n(x) measures the percentage of normal consumption of perfume when a "luxury" of x% is imposed on it, Find the rate of change of n(x) for tax of 20%; 100% and 150%.  Round the answers to two decimal places.

The given answers are -.19,-.25,-.31.

I don't even know where to start.

I presume that the first step is to state the formula in exponential terms and then to find the derivative to arrive at

-2(-0.02x^-1) -40

What do I do next?

Any help is appreciated.




So you start with

n(x) = √(12,0000- 40x- 0.02x^2)


right?

All of it is under the radical?

Use of parentheses would make things a lot easier for people to help you.
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