QUESTION 3
The figure above shows a quadratic curve and a straight line with respective equations.
= 2 + 2 + 2 and 7 − 2
The points A and B are the points of interaction between the quadratic curve and the straight line.
a) Find the coordinates of A and B.
b) Determine the exact area of the finite region bounded by the quadratic curve and the
straight line, shown shaded in the above figure.
a) = 2 + 2 + 2 = 7 − 2
= 2 + 2 + 2 = 7 − 2
= 2 + 2 − 7 + 2 + 2 = 0
= 2 − 5 + 4 = 0
( − 4), ( − 1)
= 1, = 4
A, = 7(1) − 2 , = 7(4) − 2
= 5 = 26
= (1, 5), = (4, 26)
b) 1 = (26 + 5) × 3 × 1
2
=46.5
4
2 = ∫ 2 + 2 + 2
1
=( 3 + 2 2 + 2 )14
3 2
= ( 3 + 2 + 2 )14
3
=[ 43 +42 + 2(4)] – [13 +12 + 2(1)]
33
= 42
Shaded Area = 93 − 42
2
= 4.5