document.write( "Question 968758: Please help, I posted this question earlier only to realise I had put 1π instead of 1/2π like i should have.
\n" ); document.write( "Consider the trigonometric function f (t) = −1 + 4 sin( 1/2 π(t − 1)).
\n" ); document.write( "(a) What is the amplitude of f(t)? (b) What is the period of f(t)?
\n" ); document.write( "(c) What are the maximum and minimum values attained by f(t)? (d) Sketch the graph of f (t) for t ∈ [−1, 3].
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Algebra.Com's Answer #591947 by Theo(13342)\"\" \"About 
You can put this solution on YOUR website!
the general formula for the sine function 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( "the normal period of the sine function is 2*pi.\r
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\n" ); document.write( "\n" ); document.write( "the formula for the period is:\r
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\n" ); document.write( "\n" ); document.write( "period = (2 * pi) / freqauency.\r
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\n" ); document.write( "\n" ); document.write( "when a or b or c or d are not shown, their default values are:
\n" ); document.write( "a = 1
\n" ); document.write( "b = 1
\n" ); document.write( "c = 0
\n" ); document.write( "d = 0\r
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\n" ); document.write( "\n" ); document.write( "when d = 0, the center line of the graph is at y = 0.
\n" ); document.write( "when d = -1, the center line of the graph is at y = -1.\r
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\n" ); document.write( "\n" ); document.write( "when b = 1, the period = 2 * pi divided by 1 which is equal to 2 * pi.\r
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\n" ); document.write( "\n" ); document.write( "your formula brecomes:\r
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\n" ); document.write( "\n" ); document.write( "f(t) = 4 * sin(pi/2 * x) - 1\r
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\n" ); document.write( "\n" ); document.write( "your amplitude = 4
\n" ); document.write( "your frequency = pi/2
\n" ); document.write( "your horizontal shift = 0
\n" ); document.write( "your vertical shift = -1\r
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\n" ); document.write( "\n" ); document.write( "the center line of your graph is at y = -1
\n" ); document.write( "the maximum value of your graph is -1 + 4 = 3
\n" ); document.write( "the minimum value of your graph is -1 - 4 = -5\r
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\n" ); document.write( "\n" ); document.write( "your period is equal to 2 * pi divided by pi/2.
\n" ); document.write( "this makes your period equal to 5.\r
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\n" ); document.write( "\n" ); document.write( "your horizontal shift is one unit to the right.
\n" ); document.write( "this one is a litle tricky to figure out, so we'll go through a calculation to show you what happens.\r
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\n" ); document.write( "\n" ); document.write( "your questions were:\r
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\n" ); document.write( "\n" ); document.write( "a) What is the amplitude of f(t)? \r
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\n" ); document.write( "\n" ); document.write( "the amplitude is equal to 4\r
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\n" ); document.write( "\n" ); document.write( "(b) What is the period of f(t)?\r
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\n" ); document.write( "\n" ); document.write( "the period is 4 radians\r
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\n" ); document.write( "\n" ); document.write( "(c) What are the maximum and minimum values attained by f(t)? \r
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\n" ); document.write( "\n" ); document.write( "the maximum value is f(T) = 3
\n" ); document.write( "the minimum value is f(t) = -5\r
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\n" ); document.write( "\n" ); document.write( "(d) Sketch the graph of f (t) for t ∈ [−1, 3].\r
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\n" ); document.write( "\n" ); document.write( "the graph is shown below:\r
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\n" ); document.write( "\n" ); document.write( "the period from x = -1 to x = 3 is marked between vertical dashed lines.\r
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\n" ); document.write( "\n" ); document.write( "the center line of the graph is at y = -1\r
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\n" ); document.write( "\n" ); document.write( "the maximum value is at y = 3 and the minimum value is at y = -5.\r
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\n" ); document.write( "\n" ); document.write( "you can see that the graph crosses the center line at x = -1, x = 1, x = 3 and x = 5.\r
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\n" ); document.write( "\n" ); document.write( "the center line is at y = -1.\r
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\n" ); document.write( "\n" ); document.write( "take away the vertical displacement of -1 and the center line would have been at the x-axis.\r
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\n" ); document.write( "\n" ); document.write( "you would analyze this graph as follows:\r
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\n" ); document.write( "\n" ); document.write( "when x = 3, the equation of the graph becomes:\r
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\n" ); document.write( "\n" ); document.write( "y = 4 * sin(pi/2 * (3-1)) - 1\r
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\n" ); document.write( "\n" ); document.write( "this becomes y = 4 * sin(pi/2 * 2) - 1\r
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\n" ); document.write( "\n" ); document.write( "this becomes y = 4 * sin(pi) - 1\r
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\n" ); document.write( "\n" ); document.write( "sin(pi) is equal to 0.\r
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\n" ); document.write( "\n" ); document.write( "the equation becomes y = 4 * 0 - 1\r
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\n" ); document.write( "\n" ); document.write( "it finally becomes y = -1.\r
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\n" ); document.write( "\n" ); document.write( "you can see on the graph that, when x = 3, y = -1.\r
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\n" ); document.write( "\n" ); document.write( "this agrees with the equation.\r
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\n" ); document.write( "\n" ); document.write( "we'll do one more.\r
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\n" ); document.write( "\n" ); document.write( "when x = -1, the equation of y = 4 * sin(pi/2 * (x-1)) - 1 becomes:\r
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\n" ); document.write( "\n" ); document.write( "y = 4 * sin(pi/2 * (-1-1)) - 1 which becomes:\r
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\n" ); document.write( "\n" ); document.write( "y = 4 * sin(pi/2 * -2) - 1 which becomes:\r
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\n" ); document.write( "\n" ); document.write( "y = 4 * sin(-pi) - 1 which becomes:\r
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\n" ); document.write( "\n" ); document.write( "y = 4 * 0 - 1 which becomes:\r
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\n" ); document.write( "\n" ); document.write( "y = -1.\r
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\n" ); document.write( "\n" ); document.write( "when x = -1, the value of y is equal to -1.\r
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\n" ); document.write( "\n" ); document.write( "the graph confirms that.\r
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