document.write( "Question 1085943: Please may you help me immediately to solve this problem: a.suppose the international airmail on articles/packets to countries in zone 1 are given below.
\n" ); document.write( "Weight (w) cost in kina
\n" ); document.write( "Up to 50 55
\n" ); document.write( "Up to 150 110
\n" ); document.write( "Up to 250 180
\n" ); document.write( "Up to 1kg 290
\n" ); document.write( "Up to 2kg 450\r
\n" ); document.write( "\n" ); document.write( "i.write the cost function,in function notation for the above.
\n" ); document.write( "ii.Draw the graph of this function
\n" ); document.write( "iii.state the domain and range of this function
\n" ); document.write( "iv.does the graph really represent a function? Justify you answer.
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Algebra.Com's Answer #700043 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Part i)\r
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\n" ); document.write( "\n" ); document.write( "The cost function is the piecewise function given below\r
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\n" ); document.write( "\n" ); document.write( "where w is the weight in grams, and c(w) is the cost\r
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\n" ); document.write( "\n" ); document.write( "The piecwise function basically says\r
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\n" ); document.write( "\n" ); document.write( "c(w) = 55 if \"0+%3C=+w+%3C=+50\"
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\n" ); document.write( "c(w) = 110 if \"50+%3C+w+%3C=+150\"
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\n" ); document.write( "c(w) = 180 if \"150+%3C+w+%3C=+250\"
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\n" ); document.write( "c(w) = 290 if \"250+%3C+w+%3C=+1000\"
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\n" ); document.write( "c(w) = 450 if \"1000+%3C+w+%3C=+2000\"\r
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\n" ); document.write( "\n" ); document.write( "so we have 5 separate functions depending on what w is. The notation given previously (with the big single curly brace) is a more compact way to write the piecewise function.\r
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\n" ); document.write( "\n" ); document.write( "Part ii)\r
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\n" ); document.write( "\n" ); document.write( "The graph is shown here. The graph was created with GeoGebra (free graphing software).\r
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\n" ); document.write( "\n" ); document.write( "Note how points {C, E, G, I} are open circles to indicate we do NOT include them as part of the function\r
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\n" ); document.write( "\n" ); document.write( "The graph represents a step function\r
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\n" ); document.write( "\n" ); document.write( "Part iii)\r
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\n" ); document.write( "\n" ); document.write( "Domain: set of real numbers w such that \"0+%3C=+w+%3C=+2000\"\r
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\n" ); document.write( "\n" ); document.write( "basically saying that the weights can be as small as 0 grams or as large as 2000 grams (2 kg).\r
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\n" ); document.write( "\n" ); document.write( "Range: c(w) can be only values drawn from this set: {55, 110, 180, 290, 450} \r
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\n" ); document.write( "\n" ); document.write( "Those values are the given costs for each piece of the piecewise function (see part i)\r
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\n" ); document.write( "\n" ); document.write( "Part iv)\r
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\n" ); document.write( "\n" ); document.write( "Yes it's a function because it passes the vertical line test. \r
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\n" ); document.write( "\n" ); document.write( "For any given input, there is EXACTLY ONE output. This adds further confirmation that we have a function here.
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