# Case study Chapter 8 ( Application of Integral )

**Case study 5:-A farmer has a triangular shaped field. His, son a science student observes the triangular field has three edges and can be drawn on a plain paper with three lines given by its equations.(Case study application of integral 5)**

**Based on the above information answer the following question:**

**(i) Find the area of the shaped region in the figure shown below.**

**(ii) Find the area of the triangle ΔABC.**

**Solution: We are given sides**

y = 2x – 2 ——(i)

y = 1/2(x – 1) ——-(ii)

and y = 4 – x ——-(iii)

From (i) and (ii)

2x – 2 = 1/2(x – 1)

⇒ 4x – 4 = x – 1

⇒ 3x = 3 ⇒ x = 1

Using x = 1 in (i), we get

y = 2×1 – 2 = 2 – 2 = 0

∴ A(1 , 0)

From (i) and (iii),

2x – 2 = 4 – x

⇒ 3x = 6 ⇒ x = 2

Using x = 2 in (iii), we get

y = 4 – 2 = 2

∴ B(2, 2)

From (ii) and (iii)

4 – x = 1/2(x – 1)

⇒ 8 – 2x = x – 1

⇒ 9 = 3x

⇒ x = 3

⇒ y = 4 – x = 4 – 3 = 1

∴ C(3, 1)

**(i) We have area of shaded region **

sq.units

**(ii) We have to find area of the triangle ΔABC.**

sq.units.

## Some Other Case study problem

**Case study 1: Read the following and answer the question.(Case study application of integral 1)**

Nowadays, almost every boat has a triangular sail. By using a triangular sail design it has become possible to travel against the wind using a technique known as tacking. Tacking allows the boat to travel forward with r

triangular sail on the walls and three edges(lines) at the triangular sail are given by the equation x = 0, y = 0 and y + 2x – 4 = 0 respectively.

**Solution:** For solution click here

**Case study 2: Read the following and answer the question(Case study application of integral 2)**

An architect designs a building whose lift (elevator ) is from outside of the building attached to the walls. The floor (base ) of the lift (elevator) is in semicircular shape. The floor of the elevator (lift) whose circular edge is given by the equation and the straight edge(line) is given by the equation y = 0.

**Solution:** For solution click here

**Case study 3: Read the following and answer the question(Case study application of integral 3)**

A student designs an open air Honeybee nest on the branch of a tree, whose plane figure is parabolic and the branch of tree is given by a straight line.

**Solution:** For solution click here

**Case study 4: Read the following and answer the question**

A boy design a pizza by cutting it with a knife on a card board. If pizza is circular in shape which is represented by the

equation and edge of knife represents a straight line given by .

**Solution:** for solution click here