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## Three Dimensional Geometry Class 12 Multiple Choice Test

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Thank you for answering the multiple choice test

Three Dimensional Geometry Class 12 (121101)

General Instruction:

1. There are 10 MCQ’s in the Test.

2. Passing %age is 50.

3. After time gets over, test will be submitted itself.

1 / 10

2 / 10

3 / 10

Two lines with direction ratios $$2, 1, -1$$ and $$3, -1, 2$$ are:

a) Parallel.

b) Perpendicular.

c) Skew.

d) Intersecting.

4 / 10

Which equation represents the vector equation of a line parallel to the vector $$\langle 1, -2, 3 \rangle$$ passing through the point $$(4,5,6)$$?

a) $$r = \langle 4,5,6 \rangle + \lambda \langle 1,-2,3 \rangle$$

b) $$r = \langle 4,5,6 \rangle + \lambda \langle -1,2,-3 \rangle$$

c) $$r = \langle 1,-2,3 \rangle + \lambda \langle 4,5,6 \rangle$$

d) $$r = \langle 4,5,6 \rangle + \lambda \langle 3,2,-1 \rangle$$

5 / 10

Which equation represents the Cartesian equation of a line passing through points $$P(1,2,3)$$ and $$Q(4,5,6)$$?

a) $$\frac{x-1}{3} = \frac{y-2}{3} = \frac{z-3}{3}$$

b) $$\frac{x-1}{4} = \frac{y-2}{5} = \frac{z-3}{6}$$

c) $$\frac{x-1}{3} = \frac{y-2}{3} = \frac{z-3}{4}$$

d) $$\frac{x-1}{4} = \frac{y-2}{5} = \frac{z-3}{6}$$

6 / 10

The direction ratios of a line are determined by:

a) Ratios of its equation coefficients

b) Components of its direction vector

c) Ratios of its coordinates

d) Components of its equation

7 / 10

What is the formula for finding the angle between two lines with direction cosines $$l_1, m_1, n_1$$ and $$l_2, m_2, n_2$$?

a) $$\cos^{-1}(l_1 l_2 + m_1 m_2 + n_1 n_2)$$

b) $$\cos^{-1}(l_1 + m_1 + n_1 + l_2 + m_2 + n_2)$$

c) $$\cos^{-1}\left(\frac{l_1 l_2 + m_1 m_2 + n_1 n_2}{\sqrt{l_1^2 + m_1^2 + n_1^2} \sqrt{l_2^2 + m_2^2 + n_2^2}}\right)$$

d) $$\cos^{-1}\left(\frac{l_1 + m_1 + n_1}{l_2 + m_2 + n_2}\right)$$

8 / 10

Skew lines are:

a) Parallel lines

b) Coplanar lines

c) Intersecting lines

d) Non-intersecting and non-parallel lines

9 / 10

The direction cosines of a line are given by:

a) Ratios of its coordinates

b) Components of its equation

c) Ratios of its coefficients

d) Components of its direction vector

10 / 10

What do the direction cosines of a line indicate?

a) The angles between the line and the coordinate axes.

b) The ratios of the direction components of the line.

c) The perpendicular distances from the line to the coordinate axes.

d) The inclinations of the line with the coordinate axes.