\r\n" );
document.write( "\r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "To find f(5) we substitute x=5 for x in f(x).\r\n" );
document.write( "\r\n" );
document.write( "So we have to figure out which of these 3 intervals number 5 belongs to:\r\n" );
document.write( "\r\n" );
document.write( "-7≤x<2, x=2, or x≥2 \r\n" );
document.write( "\r\n" );
document.write( "We ask the question: \"Does the number 5 fit the inequality -7≤x<2 ? \r\n" );
document.write( "The answer is NO, because 5 is not between -7 and 2, so that\r\n" );
document.write( "means that we don't use f(x)=x²+3, because we only would use that one\r\n" );
document.write( "if the value of x we wanted to substitute were between -7 and 2. \r\n" );
document.write( "\r\n" );
document.write( "We ask the question: \"Does the number 5 fit the equation x=2?\r\n" );
document.write( "No because 5 is not 2, so that means that we don't use f(x)=14, \r\n" );
document.write( "because we only would use f(x)=14 if the value of x we want \r\n" );
document.write( "to substitute were exactly 2. \r\n" );
document.write( "\r\n" );
document.write( "We ask the question: \"Does the number 5 fit the inequality x≥2 ? \r\n" );
document.write( "The answer is YES, because 5 is INDEED greater than 2, so that\r\n" );
document.write( "means that we DO use f(x)=4-3x² for that's the one we use if the value\r\n" );
document.write( "of x that we want to substitute is greater than 2, and 5 surely is\r\n" );
document.write( "greater than 2.\r\n" );
document.write( "\r\n" );
document.write( "So we substitute 5 for x in f(x)=4-3x² and we get\r\n" );
document.write( "\r\n" );
document.write( "f(5)=4-3(5)² = 4-3(25) = 4-75 = -71.\r\n" );
document.write( "\r\n" );
document.write( "Edwin
\n" );
document.write( " \n" );
document.write( "![\"\"](\"/images/stars/stars-13.gif\")
