document.write( "Question 65650: For the function defined by f(x)=2-x^2, 0 is < and = to x, I need to find a formula for f^-1(x).\r
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Algebra.Com's Answer #46337 by praseenakos@yahoo.com(507)\"\" \"About 
You can put this solution on YOUR website!
QUESTION:\r
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\n" ); document.write( "\n" ); document.write( "f(x)=2-x^2, 0 is < and = to x, I need to find a formula for f^-1(x).\r
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\n" ); document.write( "\n" ); document.write( "f(x)=2-x^2\r
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\n" ); document.write( "\n" ); document.write( "For our convenience, lets take,\r
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\n" ); document.write( "\n" ); document.write( "y = 2-x^2\r
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\n" ); document.write( "\n" ); document.write( "Rewrite the given equation as follows.\r
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\n" ); document.write( "\n" ); document.write( "Add x^2 to both sides of the equation,\r
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\n" ); document.write( "\n" ); document.write( "==> y + x^2 = 2-x^2 + x^2\r
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\n" ); document.write( "\n" ); document.write( "==> x^2 + y = 2\r
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\n" ); document.write( "\n" ); document.write( "Subtract y from both sides of the equation,\r
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\n" ); document.write( "\n" ); document.write( "==> x^2 + y - y = 2 - y\r
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\n" ); document.write( "\n" ); document.write( "==> x^2 = 2 - y\r
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\n" ); document.write( "\n" ); document.write( "Take square root on both sides of the expression,\r
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\n" ); document.write( "\n" ); document.write( "==> x = square root of ( 2 - y)\r
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\n" ); document.write( "\n" ); document.write( "We can write this expressions(after replacing y by x ) as,\r
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\n" ); document.write( "\n" ); document.write( "f-1(x) = sqrt (2-x)\r
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\n" ); document.write( "\n" ); document.write( "Which is the required inverse function.\r
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\n" ); document.write( "\n" ); document.write( "Here we can see that this inverse function is not defined when the value
\n" ); document.write( "of x is greater than 2 because then 2-x becomes a negative number and sqrt of
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\n" ); document.write( "\n" ); document.write( "So we can write, inverse of the given function is sqrt of (2-x) and x is less
\n" ); document.write( "than or equal to 2.\r
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\n" ); document.write( "\n" ); document.write( "Hope you Understood.\r
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\n" ); document.write( "\n" ); document.write( "Regards.\r
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\n" ); document.write( "\n" ); document.write( "praseenakos@yahoo.co.in\r
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