document.write( "Question 1191148: Given f(x) =-6x^2-8x
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\n" ); document.write( "Given g(x)= -12x-5
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Algebra.Com's Answer #822912 by Theo(13342)\"\" \"About 
You can put this solution on YOUR website!
problem 1:\r
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\n" ); document.write( "\n" ); document.write( "Given f(x) =-6x^2-8x, find f(f(1))\r
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\n" ); document.write( "\n" ); document.write( "f(x) = -6x^2 - 8x
\n" ); document.write( "when x = 1, f(1) = -6 -8 = -14.\r
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\n" ); document.write( "\n" ); document.write( "f(f(x)) = -6 * (-6x^2-8x)^2 - 8 * (-6x^2-8x)
\n" ); document.write( "when x = 1, -6x^2-8x = -14, therefore:
\n" ); document.write( "-f(f(1)) = -6 * (-14)^2 - 8 * -14 = -1064.\r
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\n" ); document.write( "\n" ); document.write( "your solution is that f(f(1) = -1064.\r
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\n" ); document.write( "\n" ); document.write( "this can be graphed.
\n" ); document.write( "the graph shows that the value of f(1) = -14 and the value of f(f(1)) = -1064.
\n" ); document.write( "here's the graph.
\n" ); document.write( "f(x) is in red.
\n" ); document.write( "f(f(x) is in blue\r
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\n" ); document.write( "\n" ); document.write( "problem 2:\r
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\n" ); document.write( "\n" ); document.write( "Given g(x)= -12x-5, find g^-1(5)\r
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\n" ); document.write( "\n" ); document.write( "g^-1(x) is the inverse of g(x).
\n" ); document.write( "to find it, replace g(x) with y and then replace y with x and x with y and then solve for y.
\n" ); document.write( "start with:
\n" ); document.write( "g(x) = -12x-5
\n" ); document.write( "replace g(x) with y to get:
\n" ); document.write( "y = -12x-5
\n" ); document.write( "replace y with x and x with y to get:
\n" ); document.write( "x = -12y-5
\n" ); document.write( "switch sides to get:
\n" ); document.write( "-12y-5 = x
\n" ); document.write( "add 5 to both sides to get:
\n" ); document.write( "-12y = x+5
\n" ); document.write( "divide both sides by -12 to get:
\n" ); document.write( "y = -(x+5)/12
\n" ); document.write( "replace y with g^-1(x) to get:
\n" ); document.write( "g^-1(x) = -(x+5)/12\r
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\n" ); document.write( "\n" ); document.write( "when x = 5, .....\r
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\n" ); document.write( "\n" ); document.write( "g(x) = -12x-5 becomes -12 * 5 - 5 = -65
\n" ); document.write( "g^-1(x) = -(x+5)/12 = -10/12 = -.8333\r
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\n" ); document.write( "\n" ); document.write( "g(x) and g^-1(x) can be graphed.
\n" ); document.write( "the graph is shown below.
\n" ); document.write( "in the graph, g(x) is replaced with y and g^-1(x) is replaced with y.
\n" ); document.write( "g(x) is in red.
\n" ); document.write( "g^-1(x) is in blue.\r
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\n" ); document.write( "\n" ); document.write( "let me know if you have any questions or concerns.
\n" ); document.write( "theo\r
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