document.write( "Question 1042738: Determine, without graphing, whether the given quadratic function has a maximum value or a minimum value and then find that value.\r
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document.write( "f(x) = -x2 - 2x + 2
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document.write( " a. minimum; - 1
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document.write( " b. maximum; 3
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document.write( " c. minimum; 3
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document.write( " d. maximum; - 1 \n" );
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Algebra.Com's Answer #657779 by jim_thompson5910(35256)![]() ![]() ![]() You can put this solution on YOUR website! f(x) = -x^2 - 2x + 2\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "-x^2 - 2x + 2 has the leading coefficient of -1. The negative leading coefficient means that the parabola opens downward.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "The parabola opening downward is like an upside down bowl shape. So this function has a maximum. Think of it as the peak of the mountain. \r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "In the case of -x^2 - 2x + 2, the values of a,b,c are\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "a = -1 \n" ); document.write( "b = -2 \n" ); document.write( "c = 2\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Plug a = -1 and b = -2 into x = -b/(2a) to get\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "x = -b/(2a) \n" ); document.write( "x = -(-2)/(2(-1)) \n" ); document.write( "x = -(-2)/(-2) \n" ); document.write( "x = 2/(-2) \n" ); document.write( "x = -1\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "So the max y value occurs when x = -1. Plug x = -1 into the original function to find the corresponding value of y.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "f(x) = -x^2 - 2x + 2 \n" ); document.write( "f(-1) = -(-1)^2 - 2(-1) + 2 \n" ); document.write( "f(-1) = -(1) - 2(-1) + 2 \n" ); document.write( "f(-1) = -1 - 2(-1) + 2 \n" ); document.write( "f(-1) = -1 +2 + 2 \n" ); document.write( "f(-1) = 1 + 2 \n" ); document.write( "f(-1) = 3\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "When x = -1, the corresponding y value is y = 3 \n" ); document.write( "The two values pair up to get this point (-1,3)\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "The vertex is at the point (-1,3)\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Therefore, the maximum value is y = 3 \r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "So the answer must be choice B \n" ); document.write( " |