document.write( "Question 359121: Re: Simplifying Rational Expressions and Functions
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document.write( "I understand how to write a function in simplified form using factoring and removing the factor = to 1. However, can someone walk me through the steps on determining the restrictions on the domain? I can't figure out how the restrictions on the domain are determined.
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document.write( "Write the function given by
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document.write( "g(x)= x^2+3x-10 / 2x^2-3x-2
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document.write( "in simplified form, and list all the restrictions on the domain.\r
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document.write( "Answer: g(x)= x+5/2x+1, x cannot = -1/2 and x cannot = 2\r
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document.write( "Please teach me how to determine the restrictions. Thank you. Jill \n" );
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Algebra.Com's Answer #256283 by stanbon(75887) ![]() You can put this solution on YOUR website! Write the function given by \n" ); document.write( "g(x)= x^2+3x-10 / 2x^2-3x-2 \n" ); document.write( "in simplified form, and list all the restrictions on the domain. \n" ); document.write( "Answer: g(x)= x+5/2x+1, x cannot = -1/2 and x cannot = 2 \n" ); document.write( "Please teach me how to determine the restrictions. \n" ); document.write( "--- \n" ); document.write( "1st: Factor numerator and denominator if you can. \n" ); document.write( "[(x+5)(x-2)]/[(2x+1)(x-2)] \n" ); document.write( "--- \n" ); document.write( "2nd: The function has a hole at x = 2 because you have \n" ); document.write( "the factor (x-2) in the numerator and in the denominator. \n" ); document.write( "--- \n" ); document.write( "3rd: The function is undefined at x = -1/2 because the \n" ); document.write( "factor (2x+1) is zero if x = -1/2. \n" ); document.write( "-------------- \n" ); document.write( "Comment: As you get further into algebra you will run \n" ); document.write( "into Domain restrictions for two additional reasons: \n" ); document.write( "a) Ex: y = sqrt(x+2) \n" ); document.write( "Since x+2 must not be negative, x must be >= -2. \n" ); document.write( "--- \n" ); document.write( "b) Ex: y = log(x+2) \n" ); document.write( "Since x+2 must be positive, x must be > -2. \n" ); document.write( "=============== \n" ); document.write( "Cheers, \n" ); document.write( "Stan H. \n" ); document.write( " |