document.write( "Question 337177: find (f*g)(-4) and (g*f)(-4)
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Algebra.Com's Answer #241708 by Edwin McCravy(20059)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "I fear that you are typing an asterisk * when you should be \r\n" );
document.write( "typing a small round circle ◦ which means \"composed with\",\r\n" );
document.write( "referring to the so-called \"composition\" of two functions.\r\n" );
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document.write( "f◦g(x) and f*g(x) are entirely different things.  f*g(x)\r\n" );
document.write( "means to multiply the expressions together, but f◦g(x)\r\n" );
document.write( "means to substitute what g(x) equals for x in what f(x) equals.\r\n" );
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document.write( "To get the little circle ◦ on here, type this &# 9702;  \r\n" );
document.write( "but don't skip a space between the # and the 9.  I skipped a\r\n" );
document.write( "space above so you could see what characters I typed insted\r\n" );
document.write( "of just another ◦. \r\n" );
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document.write( "find (f◦g)(-4) and (g◦f)(-4)\r\n" );
document.write( "f(x)=-2x-1; g(x)=x²+5\r\n" );
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document.write( "f◦g(-4) means f(g(-4))\r\n" );
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document.write( "So first find g(-4):\r\n" );
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document.write( "g(-4) = (-4)²+5 = 16+5 = 21\r\n" );
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document.write( "So\r\n" );
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document.write( "f◦g(-4) = f(g(-4)) = f(21) = -2(21)-1 = -42-1 = -43\r\n" );
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document.write( "g◦f(-4) means g(f(-4))\r\n" );
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document.write( "So first find f(-4):\r\n" );
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document.write( "f(-4) = -2(-4)-1 = 8-1 = 7\r\n" );
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document.write( "So\r\n" );
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document.write( "g◦f(-4) = g(f(-4)) = g(7) = (7)²+5 = 49+5 = 54\r\n" );
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document.write( "Edwin
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