Help with some homework problems PLEASE!

thomcart8

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Oct 4, 2010
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I understand what Riemann sums are I really just know how to do these problems. I could really use a lot of help. I would appreciate a full explanation too because I am not just looking for the answer. I would really like to know what is going on in these two problems. I am not very good at Calculus, in fact I am terrible at it, but i am still determined to learn what I can. I really just need for someone to give me a helping hand with these problems because I just cannot figure them out. I understand the rules of this forum, but I cannot post any work because I really don't understand what to do. Please take pity on me. I will understand if you don't since these are the rules of your site, but I really am trying to learn and you all seem to give good information. So I am begging PLEASE HELP ME!
 
You can use the chart to pick off data points. the x axis is time in hlf hour increments and the y axis is the inches of snow at those times.

time in half hours from 12 am to 6 am=(0,   .5,   1,   1.5,   2,   2.5,   3,   3.5,   4,   4.5,   5,   5.5,   6)\displaystyle \text{time in half hours from 12 am to 6 am}=(0, \;\ .5, \;\ 1, \;\ 1.5, \;\ 2, \;\ 2.5, \;\ 3, \;\ 3.5, \;\ 4, \;\ 4.5, \;\ 5, \;\ 5.5, \;\ 6)

snow fall in inches=(0,   4,   7.5,   9.5,   10,   9.5,   7.5,   5.5,   3.5,   1.75,   .75,   .25,   0)\displaystyle \text{snow fall in inches}=(0, \;\ 4, \;\ 7.5, \;\ 9.5, \;\ 10, \;\ 9.5, \;\ 7.5, \;\ 5.5, \;\ 3.5, \;\ 1.75, \;\ .75, \;\ .25, \;\ 0)

For the other parts, the graph is broken up into squares and rectangles. Count up their area on the graph. The heights are given and the width of each is 1/2.

That is essentially a Riemann sum. It is not as involved as you may think.

I used the regression on Excel to generate the 6 degree polynomial, which has an R^2=.9996. The closer R^2 is to 1 the more accurate. So, this is a pretty good fit.

It may be unwieldy to use in a Riemann sum, but it should give accurate snowfall given the time of day.

y=.0018x6.059x5+.628x42.5039x3+1.5435x2+7.8387x.0042\displaystyle y=.0018x^{6}-.059x^{5}+.628x^{4}-2.5039x^{3}+1.5435x^{2}+7.8387x-.0042

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I am not able to attach the graph of the region for the second problem. Find where a parabola intersects the two lines.
 
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