# NCERT Solutions for Class 12 Maths Exercise 9.2

NCERT Solutions for Class 12 Maths Exercise 9.2 of Differential Equations in English Medium. Download NCERT Solutions for other subjects or NCERT Solutions Apps for offline use, which work without internet.

 Class 12: Mathematics Differential Equations Exercise 9.2

## NCERT Solutions for Class 12 Maths Exercise 9.2

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### Differential Equations Solutions Exercise 9.2

#### 12 Maths Chapter 9 Exercise 9.2 Solutions

NCERT Solutions for Class 12 Maths Exercise 9.2 of Differential Equations is given below. For other exercises, please visit to 12 Maths Chapter 9 solutions page.    Visit 12 Maths Chapter 9 or Top of the page

##### Questions from Board Papers
1. Using integration, find the area of triangle ABC, whose vertices are A(2, 5), B(4, 7) and C(6, 2).
2. Find the area of the region lying above x-axis and included between the circle x2 + y2 = 8x and inside of the parabola y2 = 4x.
3. Find the vector and Cartesian equations of the plane passing through the points (2, 2 –1), (3, 4, 2) and (7, 0, 6). Also find the vector equation of a plane passing through (4, 3, 1) and parallel to the plane obtained above.
4. Find the vector equation of the plane that contains the lines r = (i + j) +µ(i + 2j – k) and the point (–1, 3, – 4). Also, find the length of the perpendicular drawn from the point (2, 1, 4) to the plane, thus obtained.

###### Some Important Questions
• A manufacturer has three machine operators A, B and C. The first operator A produces 1% of defective items, whereas the other two operators B and C produces 5% and 7% defective items respectively. A is on the job for 50% of the time, B on the job 30% of the time and C on the job for 20% of the time. All the items are put into one stockpile and then one item is chosen at random from this and is found to be defective. What is the probability that it was produced by A?
• A manufacturer has employed 5 skilled men and 10 semi-skilled men and makes two models A and B of an article. The making of one item of model A requires 2 hours work by a skilled man and 2 hours work by a semi-skilled man. One item of model B requires 1 hour by a skilled man and 3 hours by a semi-skilled man. No man is expected to work more than 8 hours per day. The manufacturer’s profit on an item of model A is ₹15 and on an item of model B is ₹10. How many of items of each model should be made per day in order to maximize daily profit? Formulate the above LPP and solve it graphically and find the maximum profit.