document.write( "Question 162729: The functions are f(x)=2x^2+5x+7 and g(x)=x^3 + 2
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document.write( "The directions say evaluate the following: and identify the domain of each
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document.write( "(f+g)(x)
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document.write( "I got x^3+2x^2+5x+9 but I dont know what the domain is. \n" );
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Algebra.Com's Answer #119965 by gonzo(654)![]() ![]() ![]() You can put this solution on YOUR website! your request: \n" ); document.write( "----- \n" ); document.write( "The functions are f(x)=2x^2+5x+7 and g(x)=x^3 + 2 \n" ); document.write( "The directions say evaluate the following: and identify the domain of each \n" ); document.write( "(f+g)(x) \n" ); document.write( "I got x^3+2x^2+5x+9 but I dont know what the domain is. \n" ); document.write( "----- \n" ); document.write( "my answer: \n" ); document.write( "----- \n" ); document.write( "f+g(x) = f(x) + g(x) \n" ); document.write( "----- \n" ); document.write( "you got it right again. \n" ); document.write( "domain is all x since nothing to make the answer imaginary or cause a division by 0. \n" ); document.write( "----- \n" ); document.write( "in general, if the domain is not specified, then the domain is whatever makes the range valid. \n" ); document.write( "there will be 4 graphs. \n" ); document.write( "scan down after each one to get the next plus any additional comments. \n" ); document.write( "----- \n" ); document.write( "graph of f+g(x) is graph of x^3+2x^2+5x+9 shown below \n" ); document.write( " \n" ); document.write( "----- \n" ); document.write( "graph of g-f(x) is graph of x^3-2x^2-5x-5 shown below \n" ); document.write( " \n" ); document.write( "----- \n" ); document.write( "graph of f*g(x) is graph of x^5 + 5x^4 + 7x^3 + 4x^2 + 10x + 14 shown below \n" ); document.write( " \n" ); document.write( "----- \n" ); document.write( "graph of f/g(x) is graph of (2x^2+5x+7)/(x^3+2) shown below \n" ); document.write( " \n" ); document.write( "it appears that the graph is good for all values of x except at \n" ); document.write( "----- \n" ); document.write( "as x^3 approaches -2 from the right (x^3 is greater than -2), the graph goes positive in a big way. \n" ); document.write( "for example: \n" ); document.write( "if you make x^3 = (-1.9999999999999), which is greater than -2, you'll see that the value of y becomes 3.86114E+13 which is a very large positive number. \n" ); document.write( "----- \n" ); document.write( "as x^3 approaches -2 from the left (x^3 is smaller than -2), the graph goes negative in a big way. \n" ); document.write( "for example: \n" ); document.write( "if you make x^3 = (-2.0000000000001). which is less than -2, you'll see that the value of y becomes -3.89561E+13 which is a very large negative number. \n" ); document.write( "----- \n" ); document.write( "the graph does not appear to be able to show this as the intervals between x values appear to be too small to be captured.\r \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |