document.write( "Question 1181096: The graph has an equation in the form of f(x) = a(1/2)^b(x+2)+k. What is the actual equation?\r
\n" ); document.write( "\n" ); document.write( "Please view the graph at:
\n" ); document.write( "https://docs.google.com/document/d/1Cl3HrcoR6jibNzxfDTIilS3imSplLY8nQUU0OpU9vLA/edit?usp=sharing
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Algebra.Com's Answer #810916 by greenestamps(13200)\"\" \"About 
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\n" ); document.write( "f(x) = a(1/2)^b(x+2)+k

\n" ); document.write( "NOTE: To make the form of the function absolutely clear, the whole exponent \"b(x+2)\" should be in parentheses: f(x) = a(1/2)^(b(x+2))+k

\n" ); document.write( "\"f%28x%29+=+a%281%2F2%29%5E%28b%28x%2B2%29%29%2Bk\"

\n" ); document.write( "Use the two given points and the horizontal asymptote to get three equations that can be solved to determine the constants a, b, and k.

\n" ); document.write( "(1) horizontal asymptote:
\n" ); document.write( "For large values of x, the decaying exponential goes to zero, making the function close to f(x)=k. Since the asymptote is y=4, we have k=4.

\n" ); document.write( "(2) f(-2) = 1:
\n" ); document.write( "\"f%28-2%29+=+a%281%2F2%29%5Eb%28-2%2B2%29%2B4\"
\n" ); document.write( "\"1+=+a%281%2F2%29%5E0%2B4\"
\n" ); document.write( "\"1+=+a%2B4\"
\n" ); document.write( "\"a=-3\"

\n" ); document.write( "(3) f(-3) = -8:
\n" ); document.write( "\"f%28-3%29+=+-3%281%2F2%29%5Eb%28-3%2B2%29%2B4\"
\n" ); document.write( "\"-8+=+-3%281%2F2%29%5Eb%28-1%29%2B4\"
\n" ); document.write( "\"-12+=+-3%282%5Eb%29\"
\n" ); document.write( "\"2%5Eb=4\"
\n" ); document.write( "\"b=2\"

\n" ); document.write( "a=-3; b=2; k=4

\n" ); document.write( "The function is

\n" ); document.write( "\"f%28x%29+=+-3%281%2F2%29%5E%282%28x%2B2%29%29%2B4\"

\n" ); document.write( "A graph:

\n" ); document.write( "\"graph%28400%2C400%2C-4%2C4%2C-6%2C6%2C-3%281%2F2%29%5E%282%28x%2B2%29%29%2B4%29\"
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