Find the area of the triangle with vertices A(1, 1, 2), B(2, 3, 5) and C(1, 5, 5).

Mathematics Part-II

Book: Mathematics Part-II

Chapter: 10. Vector Algebra

Subject: Maths - Class 12^th

Q. No. 9 of Exercise 10.4

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9

Find the area of the triangle with vertices A(1, 1, 2), B(2, 3, 5) and C(1, 5, 5).

So,

Now we want to find the

Now we want to find the

We know that

So, we find first.

Expanding along first row,

9

Chapter Exercises

Exercise 10.1

Exercise 10.2

Exercise 10.3

Exercise 10.4

Miscellaneous Exercise

1

Find if

2

Find a unit vector perpendicular to each of the vector

3

If a unit vector makes angles and an acute angle θ with then find θ and hence, the components of .

4

Show that

5

Find λ and μ if

6

Given that What can you conclude about the vectors ?

7

Let the vectors be given as Then show that

8

If either then Is the converse true? Justify your answer with an example.

9

Find the area of the triangle with vertices A(1, 1, 2), B(2, 3, 5) and C(1, 5, 5).

10

Find the area of the parallelogram whose adjacent sides are determined by the vectors

11

Let the vectors be such that then is a unit vector, if the angle between is

12

Area of a rectangle having vertices A, B, C and D with position vectors respectively is