FUNCTIONS D1

Find the maximum value of the quadratic equation:3-6t-8t².

 

Solution

 

a=-8, b=-6, c=3

 

Maximum = 4ac-b²

                        4a

 

Maximum = (4 x -8 x 3) - (-6)²

                          4(-8)

 

Maximum = (-96)- 36

                         32

 

Maximum= -132                         since (-96)- 36=-132

                     32

 

Maximum = -66 =  -33 

                     16       8    

 

Hence maximum value is -33/8

 

TRY THIS………………………………..

 

NECTA  2003 QN. 10c

 

Find the maximum value of the quadratic equation:3+30t-5t².