document.write( "Question 607375: The depth of the water at the end of a boat dock is given by:\r
\n" ); document.write( "\n" ); document.write( "y=3sin[2pi/12 (x+3)] +9, where x is the number of hours after midnight.\r
\n" ); document.write( "\n" ); document.write( "a. What is the amplitude?
\n" ); document.write( "b. What is the period?
\n" ); document.write( "c. What is the phase shift?
\n" ); document.write( "d. Sketch the graph of function for one full period starting with midnight.
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Algebra.Com's Answer #382722 by lwsshak3(11628)\"\" \"About 
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The depth of the water at the end of a boat dock is given by:
\n" ); document.write( "y=3sin[2pi/12 (x+3)] +9, where x is the number of hours after midnight.
\n" ); document.write( "a. What is the amplitude?
\n" ); document.write( "b. What is the period?
\n" ); document.write( "c. What is the phase shift?
\n" ); document.write( "d. Sketch the graph of function for one full period starting with midnight
\n" ); document.write( "**
\n" ); document.write( "Equation of sin function: Asin(Bx-C), A=amplitude, Period=2π/B, Phase shift=C/B
\n" ); document.write( "Rewrite given equation:
\n" ); document.write( "y=3sin[2pi/12 (x+3)] +9
\n" ); document.write( "=3sin[π/6 (x+3)] +9
\n" ); document.write( "=3sin[πx/6+π/2] +9
\n" ); document.write( "..
\n" ); document.write( "Amplitude=3
\n" ); document.write( "B=π/6
\n" ); document.write( "Period=2π/B=2π/(π/6)=12 hrs
\n" ); document.write( "1/4 period=3
\n" ); document.write( "C=π/2
\n" ); document.write( "Phase shift=C/B=(π/2)/(π/6)=3 hrs (shift left)
\n" ); document.write( "..
\n" ); document.write( "Graph function for one period:
\n" ); document.write( "I don't have the means to draw a graph but I will develop the (x,y) coordinates with which you can use to draw a graph for one period.
\n" ); document.write( "..
\n" ); document.write( "Start with coordinates of basic sin function: sin(πx/6) (x-axis scaled in hours)
\n" ); document.write( "(0,0), (3,1), (6,0), (9,-1), (12,0)
\n" ); document.write( "Include amplitude: 3sin(πx/6)
\n" ); document.write( "(0,0), (3,3), (6,0), (9,-3), (12,0)
\n" ); document.write( "Shift 3 hrs left: 3sin(πx/6+π/2)
\n" ); document.write( "(-3,0), (0,3), (3,0), (6,-3), (9,0),(12,3)
\n" ); document.write( "Bump curve up 9 units:3sin(πx/6+π/2)+9 (final configuration)
\n" ); document.write( "(-3,9), (0,12), (3,9), (6,6), (9,9), (12,12)
\n" ); document.write( "..
\n" ); document.write( "y-intercept
\n" ); document.write( "set x=0
\n" ); document.write( "y=3sin(πx/6+π/2)+9
\n" ); document.write( "y=3(sinπ/2)+9
\n" ); document.write( "y=3*1+9=12
\n" ); document.write( "You now have the y-intercept and the (x,y) coordinates with which you can draw graph of given sin function. One full period starts at (0,12) and ends at (12,12)
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