document.write( "Question 1140384: please explain:
\n" ); document.write( "Determine whether f(x)=6/(x+5) is one-to-one. If it is one-to-one, find a formula for the inverse.
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Algebra.Com's Answer #760906 by MathLover1(20849)\"\" \"About 
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\n" ); document.write( "In order to show that \"f%28x%29\" is one-to-one, we need to show that if \"f%28x%5B1%5D%29=f%28x%5B2%5D%29\", then \"x%5B1%5D=x%5B2%5D\". \r
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\n" ); document.write( "\n" ); document.write( "In other words, we need to show that each \"y\" value ONLY has ONE unique \"x\" value mapping to it.
\n" ); document.write( "In this case, we're assuming that \"x%5B1%5D\" and \"x%5B2%5D\" are two different values that map to the same \"y+\"}value (but as you'll see, they are in fact the same value)\r
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\n" ); document.write( "\n" ); document.write( "\"f%28x%5B1%5D%29=f%28x%5B2%5D%29\" Start with the given equation\r
\n" ); document.write( "\n" ); document.write( "\"6%2F%28x%5B1%5D%2B5%29=6%2F%28x%5B2%5D%2B5%29\" ...divide by \"6\"\r
\n" ); document.write( "\n" ); document.write( "\"1%2F%28x%5B1%5D%2B5%29=1%2F%28x%5B2%5D%2B5%29\" .......cross multiply\r
\n" ); document.write( "\n" ); document.write( "\"%28x%5B2%5D%2B5%29=%28x%5B1%5D%2B5%29\" .......cancel \"5\"\r
\n" ); document.write( "\n" ); document.write( "\"x%5B2%5D=x%5B1%5D\" \r
\n" ); document.write( "\n" ); document.write( "So we've shown that if \"f%28x%5B1%5D%29=f%28x%5B2%5D%29\", then \"x%5B1%5D=x%5B2%5D\". This means that \"f%28x%29\" is one-to-one.\r
\n" ); document.write( "\n" ); document.write( "now, find a formula for the inverse:\r
\n" ); document.write( "\n" ); document.write( "\"f%28x%29+=+6%2F%28x+%2B+5%29+\"........recall that \"f%28x%29=y\"\r
\n" ); document.write( "\n" ); document.write( "\"y=+6%2F%28x+%2B+5%29+\".......swap \"x\" and \"y\"\r
\n" ); document.write( "\n" ); document.write( "\"x=+6%2F%28y+%2B+5%29+\".........solve for \"y\"\r
\n" ); document.write( "\n" ); document.write( "\"x%28y+%2B+5%29+=+6\"\r
\n" ); document.write( "\n" ); document.write( "\"y+%2B+5+=+6%2Fx\"\r
\n" ); document.write( "\n" ); document.write( "\"y++=+6%2Fx-5\"\r
\n" ); document.write( "\n" ); document.write( "\"f%5E-1%28x%29+=++6%2Fx-5\"\r
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\n" ); document.write( "\n" ); document.write( "\"+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C+6%2F%28x%2B5%29%2C+6%2Fx-5%29+\" \r
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