document.write( "Question 1194085: A firm estimates that it can sell Q units of its product with an advertising expenditure of x thousand dollars where \r
\n" ); document.write( "\n" ); document.write( "Q = Q(x) = - x ^ 2 + 600x + 25\r
\n" ); document.write( "\n" ); document.write( "i) Over what level of advertising expenditure is the number of units of product sold increasing?\r
\n" ); document.write( "\n" ); document.write( " ii) Over what level of advertising expenditure is the number of units of product sold decreasing? \n" ); document.write( "

Algebra.Com's Answer #826182 by ikleyn(52803) $\"\"$ $\"About$

You can put this solution on YOUR website!
.
\n" ); document.write( "

\r\n" );
document.write( "\r\n" );
document.write( "The roots of this quadratic function are  ,\r\n" );
document.write( "\r\n" );
document.write( "or  -0.042  and  600.042, approximately.\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "So, the domain of the function (the area, where it is meaningful) is this interval  [0,600.042].\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "The function is a downward parabola with the maximum at \"  \" =  = 300.\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "So, over the interval  [0,300)  the function is increasing;  over the interval  (300,600.042]  it is decreasing.    ANSWER\r\n" );
document.write( "

\r
\n" ); document.write( "\n" ); document.write( "Solved.\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

\n" );