Find the area of the region bounded by the curve (y-1)2=4(x+1) and the line y=x-1.
Given the boundaries of the area O befound are,
• Curve is (y-1)2 = 4 (x+1)
• Line y = x-1
Consider the curve
(y-1)2 = 4 (x+1)
Substitute y = x-1
(x-1-1)2 = 4(x+1)
(x-2)2 = 4x+ 4
x2 – 4x + 4 = 4x + 4
x2 – 8x = 0
x(x-8) =0
x = 8 (or) x = 0
substituting x in y = x-1
y = 7 (or) y = -1
So , the parabola meets the line y = x-1 at 2 points, D (8,7) and E (0,-1)
As per the given boundaries,
• The parabola (y-1)2 = 4 (x+1), with vertex at B(-1,1).
• Line y = x-1
The boundaries of the region to be found are,
•Point B, where the curve (y-1)2 = 4 (x+1) has the extreme end the vertex i.e. B (-1,1)
•Point D, where the curve (y-1)2 = 4 (x+1) and the line y= x + 1 meet i.e. D (8,7)
•Point E, where the curve (y-1)2 = 4 (x+1) and the line y = x-1 meet i.e. E (0,-1)
•Point O, the origin
Consider the parabola,
(y-1)2 = 4(x+1)
Area of the required region = Area of EABCDE
Area of EABCDE = Area above line ED - Area above EABCD
[Using the formula ]
The Area of the required region