At vero eos et accusamus et iusto odio dignissimos ducimus qui blanditiis praesentium voluptatum deleniti atque corrupti quos dolores et quas molestias excepturi sint occaecati cupiditate non provident, similique sunt in culpa qui officia deserunt mollitia animi, id est laborum et dolorum fuga. Et harum quidem rerum facilis est et expedita distinctio. Nam libero tempore, cum soluta nobis est eligendi optio cumque nihil impedit quo minus id quod maxime placeat facere possimus, omnis voluptas assumenda est, omnis dolor repellendus. Itaque earum rerum hic tenetur a sapiente delectus, ut aut reiciendis voluptatibus maiores alias consequatur aut perferendis doloribus asperiores repellat.
what do you get for dA/dr ?
Use a order of operation. PEMDAS First to do is the paratheis
you need to find the derivative of A
How do I find a derivative of something with no variable?
the variable is r
yes the variable is r, and r is 4
that's not the way to do this you need to find a rate of change so you differentiate
You are working out A not dA/dr
how would I work our dA/dr?
dA / dr = 2700* 96(1 + r/1200)^95 * 1/1200
- use the chain rule
so plug in r = 4 and you have your answer
You'll need a calculator for that , of course
It comes to one of the choices
If you have a graphical calculator you can just type it in as above otherwise it might be better to work out the parentheses first then the exponential (^95), then multiply by 2700 , by 96 and then divide by 1200
Wow, I have no idea how you figured out how to do it like that, but it works. I will be thinking about this one all day. Thanks
the derivative dA/dr gives you the rate of change of area with respect to r. by plugging in r = 4 you get the rate of change when r = 4.