document.write( "Question 126910: Hi could you help me solve his problem. The section im working on is graphing square root and other radicals functions.\r
\n" ); document.write( "\n" ); document.write( " The formula t=2(pi symbol)square root of (L/9.8)
\n" ); document.write( "can be used to estimate the number of seconds t it takes a pendulum of length L meters to make one complete swing. Graph the equation on a graphing calculator. Then use the graph to estimate the values of t for pendulums of lengths 1.5 meters and 2.5 meters. (1 point)\r
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Algebra.Com's Answer #92961 by bucky(2189)\"\" \"About 
You can put this solution on YOUR website!
Let t (the number of seconds for 1 complete swing of the pendulum) be represented on the
\n" ); document.write( "vertical axis (y-axis). And let L (the length of the pendulum arm in meters) be represented
\n" ); document.write( "on the horizontal axis (x-axis)
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\n" ); document.write( "You can easily calculate a couple of points on the graph of:
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\n" ); document.write( "\"t+=+2%2Api%2Asqrt%28L%2F9.8%29\"
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\n" ); document.write( "just to check what your calculator shows as the graph. First you can tell that L has to be
\n" ); document.write( "a positive value. Why? Because if it were negative you would be taking the square root of
\n" ); document.write( "a negative number and this means that the answer would not be a real number. (Also it doesn't make
\n" ); document.write( "sense that a pendulum would involve a negative length.)
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\n" ); document.write( "What if L is zero? If you substitute zero for L in the equation, the square root term becomes zero
\n" ); document.write( "and this makes the whole right side of the equation become zero. So when L = 0 then t also
\n" ); document.write( "equals zero. This means that the point (0,0) is on the graph. Note that this is just a
\n" ); document.write( "mathematical solution. It really makes no sense to have a pendulum with an arm of zero length.
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\n" ); document.write( "What if L is 9.8? Then the term in the radical becomes 1 and the square root is 1. This
\n" ); document.write( "makes the right side of the equation become:
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\n" ); document.write( "\"t+=+2%2Api%2A1+=+2%2Api\"
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\n" ); document.write( "and \"2%2Api\" is approximately 6.28. So the point (L, t) is (9.8, 6.28) and it should be
\n" ); document.write( "on the graph.
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\n" ); document.write( "These are points on the graph just to help us get a feel that our graph is correct.
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\n" ); document.write( "When you do the graph on your calculator it should look like this:
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\n" ); document.write( "\"graph%28600%2C600%2C-3%2C15%2C-3%2C10%2C2%2A3.141592654%2Asqrt%28x%2F9.8%29%29\"
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\n" ); document.write( "Note that (0,0) is a point on the graph. And when you go to 9.8 on the horizontal
\n" ); document.write( "axis, the corresponding value in the vertical direction appears to be 6.28 just as we had
\n" ); document.write( "said. The graph appears to be correct.
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\n" ); document.write( "Now all you have to do to answer the problem is:
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\n" ); document.write( "First, go out to 1.5 on the horizontal axis and determine how many vertical units you have to go
\n" ); document.write( "up to get to the graph. (You should get an answer of about 2.458 seconds.)
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\n" ); document.write( "Then go out to 2.5 on the horizontal and determine from that point how many vertical units
\n" ); document.write( "you have to go up to get to the graph. (You should get an answer of about 3.173 seconds.)
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\n" ); document.write( "Hope this helps you to understand the problem and how to solve it.
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