document.write( "Question 1054031: If h(x)=2f(x+1)-g(x-1) what is,the value of h(3)?
\n" ); document.write( "This is my work so far:
\n" ); document.write( "2f(3+1)-g(3-1)
\n" ); document.write( "2f(4)-g(2)
\n" ); document.write( "8f-2g \n" ); document.write( "
Algebra.Com's Answer #669242 by Edwin McCravy(20056)\"\" \"About 
You can put this solution on YOUR website!
If \"h%28x%29=2f%28x%2B1%29-g%28x-1%29\" what is the value of \"h%283%29\"?
\n" ); document.write( "This is my work so far:
\n" ); document.write( "\"2f%283%2B1%29-g%283-1%29\"
\n" ); document.write( "\"2f%284%29-g%282%29\"
\n" ); document.write( "\"cross%288f-2g%29\"
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document.write( "It was OK until your last step.  However  \r\n" );
document.write( "h(x) does NOT mean h times x, nor h∙x nor hx.\r\n" );
document.write( "f(4) does NOT mean f times 4 nor 4∙f nor 4f.\r\n" );
document.write( "g(2) does NOT mean g times 2 nor 2∙g nor 2g.\r\n" );
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document.write( "Unless you are given equations for f(x) and g(x),\r\n" );
document.write( "the final answer is 2f(4)-g(2).  You stop there.\r\n" );
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document.write( "Although you were taught that f(x) means f times x\r\n" );
document.write( "in first year algebra, in college algebra it does \r\n" );
document.write( "not mean multiplication!\r\n" );
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document.write( "In college algebra, a single letter with a parentheses \r\n" );
document.write( "just to the right of it usually means functional notation. \r\n" );
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document.write( "f(x) is read \"f of x\".\r\n" );
document.write( "f(4) is read \"f of 4\".\r\n" );
document.write( "g(2) is read \"g of 2\".\r\n" );
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document.write( "If you were given equations, say, \r\n" );
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document.write( "f(x) = 2x-3 \r\n" );
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document.write( "g(x) = 5x+1\r\n" );
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document.write( "h(x) = 2f(x+1)-g(x-1)\r\n" );
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document.write( "This is how you would proceed.\r\n" );
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document.write( "You would do what you did above:\r\n" );
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document.write( "h(3) = 2f(3+1)-g(3-1)\r\n" );
document.write( "h(3) = 2f(4)-g(2)\r\n" );
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document.write( "But then you would find f(4) by substituting \r\n" );
document.write( "4 for x in the equation for f(x):\r\n" );
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document.write( "f(x) = 2x-3\r\n" );
document.write( "f(4) = 2(3)-3 = 6-3 = 3\r\n" );
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document.write( "And then you would find g(2) by substituting \r\n" );
document.write( "2 for x in the equation for g(x):\r\n" );
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document.write( "g(x) = 5x+1\r\n" );
document.write( "g(2) = 5(2)+1 = 10+1 = 11\r\n" );
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document.write( "And then substitute 3 for f(4) and 11 for g(2) in\r\n" );
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document.write( "h(3) = 2f(4)-g(2)\r\n" );
document.write( "h(3) = 2(3)-11  \r\n" );
document.write( "h(3) = 6-11\r\n" );
document.write( "h(3) = -5\r\n" );
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document.write( "A number with a parentheses just after it DOES mean\r\n" );
document.write( "multiplication in both first year algebra and college\r\n" );
document.write( "algebra.  However when you see a letter with a parentheses\r\n" );
document.write( "after it, such as f(x), g(x), or t(x), it usually \r\n" );
document.write( "means to substitute what is in the parentheses for \r\n" );
document.write( "x in the given equation for f(x), g(x), or t(x).\r\n" );
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document.write( "I realize this may get some getting used to.  \r\n" );
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document.write( "When you see a college algebra problem like this:\r\n" );
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document.write( "Given f(x) = 4x-3, find f(7),\r\n" );
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document.write( "it is the same problem as the first year algebra problem:\r\n" );
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document.write( "Given y = 4x-3, find y when x = 7.\r\n" );
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document.write( "The answer to both problems would be 25.\r\n" );
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document.write( "Hope this helps you.\r\n" );
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document.write( "Edwin
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