document.write( "Question 74163: hi, i am needing help with this question from a hand out..\r
\n" ); document.write( "\n" ); document.write( "f:R to R is defined by f(x)=2x+1 then f^-1=\r
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\n" ); document.write( "\n" ); document.write( "i came up with 2x-1 as my answer..can you help verify? thanks \n" ); document.write( "

Algebra.Com's Answer #53386 by jim_thompson5910(35256) $\"\"$ $\"About$

You can put this solution on YOUR website!
First switch the x and y variables
\n" ); document.write( " $\"y=2x%2B1\"$ -> $\"x=2y%2B1\"$ and then solve for y to find the inverse function
\n" ); document.write( " $\"x-1=2y%2Bcross%281-1%29\"$
\n" ); document.write( " $\"%28x-1%29%2F2=%28cross%282%29y%29%2Fcross%282%29\"$ Divide both sides by 2
\n" ); document.write( " $\"y=%281%2F2%29x-%281%2F2%29\"$ There's the inverse function.
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\n" ); document.write( "To check this let x=1 and plug it into the original equation
\n" ); document.write( " $\"y=2%281%29%2B1\"$
\n" ); document.write( " $\"y=2%2B1\"$
\n" ); document.write( " $\"y=3\"$
\n" ); document.write( "Take this answer and plug it into the inverse function
\n" ); document.write( " $\"y=%281%2F2%29%283%29-%281%2F2%29\"$
\n" ); document.write( " $\"y=%283%2F2%29-%281%2F2%29\"$
\n" ); document.write( " $\"y=%282%2F2%29\"$
\n" ); document.write( " $\"y=1\"$
\n" ); document.write( "Since you got the number you originally plugged in (which was 1) this shows us that this is the inverse function. \n" ); document.write( "

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