JEE MAIN - Mathematics (2021 - 1st September Evening Shift - No. 9)

The distance of line $$3y - 2z - 1 = 0 = 3x - z + 4$$ from the point (2, $$-$$1, 6) is :
$$\sqrt {26} $$
$$2\sqrt 5 $$
$$2\sqrt 6 $$
$$4\sqrt 2 $$

Explanation

$$3y - 2z - 1 = 0 = 3x - z + 4$$

$$3y - 2z - 1 = 0$$

D.R's $$\Rightarrow$$ (0, 3, $$-$$2)

$$3x - z + 4$$ = 0

D.R's $$\Rightarrow$$ (3, $$-$$1, 0)

Let DR's of given line are a, b, c

Now, 3b $$-$$ 2c = 0 & 3a $$-$$ c = 0

$$\therefore$$ 6a = 3b = 2c

a : b : c = 3 : 6 : 9

Any point on line

3K $$-$$ 1, 6K + 1, 9K + 1

Now, 3(3K $$-$$ 1) + 6(6K + 1)1 + 9(9K + 1) = 0

$$\Rightarrow$$ K = $${1 \over 3}$$

Point on line $$\Rightarrow$$ (0, 3, 4)

Given point (2, $$-$$1, 6)

$$\Rightarrow$$ Distance = $$\sqrt {4 + 16 + 4} = 2\sqrt 6 $$

Option (c)

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