document.write( "Question 1003122: Find the domain and range of the following function in interval form.\r
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document.write( "f(x)= *
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Algebra.Com's Answer #619931 by Theo(13342)![]() ![]() You can put this solution on YOUR website! without graphing these equations, you wouldn't have been able to see what is going on.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "first i graphed sqrt(x^2 + 3x - 4)\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "that graph is shown below:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " ![]() \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "then i graphed sqrt(2 - x - x^2)\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "that graph is shwon below:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " ![]() \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "then i graphed both together on the same graph.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "that graph is shown below:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " ![]() \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "then i graphed sqrt(x^2 + 3x - 4) * (2 - x - x^2)\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "that graph is shown below:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " ![]() \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "what happens is that the last graph shows nothing.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the reason for this is that the only valid interval for the graph of (2 - x - x^2) is within the invalid interval of (x^2 + 3x - 4) so it disappears.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the exclusion zone for the first expression is -4 < x < 1.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the exclusion zone for the second expression is x < -2 and x > 1.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "put those 2 exclusion zones together and you have the entire domain of x being excluded which results in a null graph.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "it took a little bit of analysis to figure this out algebraically.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "first the expressions needed to be factored.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "then the factors were analyzed to determine when the value under the square root sign became negative.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "in order for sqrt((x+4)*(x-1)) to be negative, (x+4) had to be positive while (x-1) was negative and (x+4) had to be negative when (x-1) was positive.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "in order for sqrt((2+x)*(1-x)) to be negative, (2+x) has to be positive while (1-x) was negative and (2+x) had to be negative when (1-x) was positive.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the analysis confirmed what was shown on the graph.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "sqrt((x+4)*(x-1)) was negative when -4 < x < 1\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "sqrt((2+x)*(1-x)) was negative when x < -2 and x > 1.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "sqrt((x+4)*(x-1)) was positive when x <= -4 and x >= 1\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "sqrt((2+x)*(1-x)) was positive when -2 <= x < 1\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "when you put them together on the same grpah, their exclusion zones together comprised all values of x so there were not values of x that could be graphed.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the domain was therefore null.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "that's what i believe is happening.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the graphs confirmed it.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the analysis was fairly length but and a little bit complex, but it confirmed what the graphs showed.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "i didn't show the analysis because it would have complicate the results of the analysis unnecessarily and i didn't have enough time to finish it.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "if you need a better explanation, then write and i'll take the time tomorrow or the next day to work it out for you.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "you should, however, be able to work it out for yourself, now that you know what's happening and how you need to proceed.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the graphing software i used is at link to calculator used\r \n" ); 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