document.write( "Question 201168This question is from textbook Intermediate algebra an applied approach
\n" ); document.write( ": Find the maximum or minimum value of f(x)= -3x^2 +4x-1 \n" ); document.write( "
Algebra.Com's Answer #151377 by RAY100(1637)\"\" \"About 
You can put this solution on YOUR website!
y= -3x^2 +4x -1
\n" ); document.write( ".
\n" ); document.write( "differentiate and set equal to zero
\n" ); document.write( ".
\n" ); document.write( "y' = -6x +4
\n" ); document.write( ".
\n" ); document.write( "-6x +4 =0
\n" ); document.write( ".
\n" ); document.write( "-6x =-4
\n" ); document.write( ".
\n" ); document.write( "x= 2/3,,,,,,,
\n" ); document.write( ".
\n" ); document.write( "substitute into original eqn
\n" ); document.write( ".
\n" ); document.write( "y = -3(2/3)^2 +4(2/3) -1
\n" ); document.write( ".
\n" ); document.write( "y= -3 (4/9) +8/3 -3/3
\n" ); document.write( ".
\n" ); document.write( "y= -4/3 +8/3 -1/3
\n" ); document.write( ".
\n" ); document.write( "y = 1/3,,,,,,,,
\n" ); document.write( ".
\n" ); document.write( "Checking points in proximity, ( 0,-1) and (1,0) confirm a downward pointing y parabola , with a vertex at (2/3,1/3) which is a max
\n" ); document.write( ".
\n" ); document.write( " \n" ); document.write( "
\n" );