document.write( "Question 920439: Find the amplitude, Period, Phase Shift, Graph and max/min and x and y intercepts of:\r
\n" ); document.write( "\n" ); document.write( "g(t) = -2sin(πt + π/3)\r
\n" ); document.write( "\n" ); document.write( "Please give a detailed answer for this. I think I understand the amplitude being the height from the negative or positive of the y axis. And therefore it would be from 2 to -2? And it's always the absolute of the first number.\r
\n" ); document.write( "\n" ); document.write( "The period I think is the number of times It goes around and I think that is the π/3 part\r
\n" ); document.write( "\n" ); document.write( "The phase shift not sure\r
\n" ); document.write( "\n" ); document.write( "and how to find the max and min, not sure
\n" ); document.write( "or the x and y intercepts.\r
\n" ); document.write( "\n" ); document.write( "Please help
\n" ); document.write( "Thank you
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Algebra.Com's Answer #558393 by Theo(13342)\"\" \"About 
You can put this solution on YOUR website!
the general formula is:\r
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\n" ); document.write( "\n" ); document.write( "y = a*(sin(b(x-c))+d\r
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\n" ); document.write( "\n" ); document.write( "|a| is the amplitude
\n" ); document.write( "b is the frequency
\n" ); document.write( "c is the horizontal shift
\n" ); document.write( "d is the vertical shift.\r
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\n" ); document.write( "\n" ); document.write( "replace t with x and your equation is:\r
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\n" ); document.write( "\n" ); document.write( "y = -2 * sin( pi * x + pi/3)\r
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\n" ); document.write( "\n" ); document.write( "this can also be written as:\r
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\n" ); document.write( "\n" ); document.write( "y = -2 * sin( pi * (x + 1/3))\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "the general equation is, once again:\r
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\n" ); document.write( "\n" ); document.write( "y = a * (sin( b * (x-c)) + d\r
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\n" ); document.write( "\n" ); document.write( "in your equation:\r
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\n" ); document.write( "\n" ); document.write( "|a| = 2
\n" ); document.write( "b = pi
\n" ); document.write( "c = 1/3
\n" ); document.write( "d = 0\r
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\n" ); document.write( "\n" ); document.write( "your amplitude is equal to 2
\n" ); document.write( "your frequency is equal to pi
\n" ); document.write( "your horizontal shift is equal to -1/3
\n" ); document.write( "your vertical shift is equal to 0\r
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\n" ); document.write( "\n" ); document.write( "your period is equal to 2*pi divided by your frequency.
\n" ); document.write( "this makes your period equal to 2*pi / pi = 2\r
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\n" ); document.write( "\n" ); document.write( "everything is in radians.\r
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\n" ); document.write( "\n" ); document.write( "your equation looks like this:\r
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\n" ); document.write( "\n" ); document.write( "\"picture\r
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\n" ); document.write( "\n" ); document.write( "the period is equal to 2 and goes from -1/3 to 5/3.
\n" ); document.write( "your amplitude is equal to 2 so the graph goes from a high of 2 to a low of -2.
\n" ); document.write( "there is no vertical shift because d = 0.\r
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\n" ); document.write( "\n" ); document.write( "take away the horizontal shift and your graph looks like this:\r
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\n" ); document.write( "\n" ); document.write( "\"picture\r
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\n" ); document.write( "\n" ); document.write( "everything else remains the same except there is no more horizontal shift so the period goes from 0 to 2.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "your y intercept is the value of y when x = 0.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "your equation is, once again:\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "y = -2 * sin( pi * (x + 1/3))\r
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\n" ); document.write( "\n" ); document.write( "when x = 0, y = -2 * sin(pi/3)\r
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\n" ); document.write( "\n" ); document.write( "pi/3 = 60 degrees and sin (60) = sqrt(3)/2\r
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\n" ); document.write( "\n" ); document.write( "-2*sqrt(3)/2) = -sqrt(3) which is equivalent to -1.73.....\r
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\n" ); document.write( "\n" ); document.write( "you can see that on the following graph.\r
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\n" ); document.write( "\n" ); document.write( "that's the value of y when x = 0\r
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\n" ); document.write( "\n" ); document.write( "\"picture\r
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\n" ); document.write( "\n" ); document.write( "the x-intercept is the value of x when y = 0\r
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\n" ); document.write( "\n" ); document.write( "set your equation and solve for x.\r
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\n" ); document.write( "\n" ); document.write( "you get:\r
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\n" ); document.write( "\n" ); document.write( "0 = -2sin(pi(x+1/3))\r
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\n" ); document.write( "\n" ); document.write( "divide both sides by -2 and you get:\r
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\n" ); document.write( "\n" ); document.write( "sin(pi(x+1/3) = 0\r
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\n" ); document.write( "\n" ); document.write( "this is true if and only if arc-sine(0) = pi(x+1/3)\r
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\n" ); document.write( "\n" ); document.write( "arc-sin(0) = 0 so pi(x+1/3) = 0 which results in x = -1/3.\r
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\n" ); document.write( "\n" ); document.write( "the value of y is 0 when x = -1/3.\r
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\n" ); document.write( "\n" ); document.write( "\"picture\r
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\n" ); document.write( "\n" ); document.write( "here's a good reference on the general formula used.\r
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\n" ); document.write( "\n" ); document.write( "http://www.regentsprep.org/regents/math/algtrig/ATT7/sinusoidal.htm\r
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