document.write( "Question 1028867: Find the inverse function of f:[3,∞) -> R, f(x) = (x-4)^2 +1
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Algebra.Com's Answer #643929 by josgarithmetic(39618)\"\" \"About 
You can put this solution on YOUR website!
Look first for the inverse relation to f.\r
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\n" ); document.write( "\n" ); document.write( "\"%28R%28x%29-4%29%5E2%2B1=x\" for the inverse function of f.
\n" ); document.write( "\"%28R%28x%29-4%29%5E2=x-1\"
\n" ); document.write( "\"R%28x%29-4=0%2B-+sqrt%28x-1%29\"
\n" ); document.write( "\"R%28x%29=4%2B-+sqrt%28x-1%29\"\r
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\n" ); document.write( "\n" ); document.write( "The domain of R(x) is for TWO different functions. R itself is a relation and not a function. This is because the \"plus or minus\" part of the expression. The domain for either branch of R is \"x%3E=4\".\r
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\n" ); document.write( "\n" ); document.write( "Look again at function f(x). Domain is ALL REAL NUMBERS. What about the range of f(x)? f(x) is a parabola with a vertex minimum value at (4,1). This means that the RANGE for f(x) is \"x%3E=4\", or as a description, from 4 inclusive toward infinity. \r
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\n" ); document.write( "\n" ); document.write( "Going from a function (f(x)) to its inverse, the domain and range switch. The range \"x%3E=4\" for f(x) is the DOMAIN for either branch of R(x).\r
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\n" ); document.write( "\n" ); document.write( "Function f(x)
\n" ); document.write( "\"graph%28300%2C300%2C-3%2C12%2C-3%2C12%2C%28x-4%29%5E2%2B1%29\"\r
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\n" ); document.write( "\n" ); document.write( "Upper branch of R(x)
\n" ); document.write( "\"graph%28300%2C300%2C-3%2C12%2C-7%2C8%2C-4%2Bsqrt%28x-1%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "Lower branch of R(x)
\n" ); document.write( "\"graph%28300%2C300%2C-3%2C12%2C-7%2C8%2C-4-sqrt%28x-1%29%29\"
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