The angle between the pairs of lines r = (3i + 2j - 4k) + (i + 2j + 2k) r = (5i - 2j) + (3i + 2j + 6k) is : Option 1: = ^-1(sqrt(19)21) Option 2: = ^-1(sqrt(19)sqrt(21)) Option 3: = ^-1(19/21) Option 4: = ^-1(9/21)

The answer is '= ^-1(19/21)'. View full solution:

CUET Mathematics - The angle between the pairs of lines r = (3i + 2j - 4k) + (i + 2j + 2k) r = (5i - 2j) + (3i + 2j + 6k) is : | PYQs + Solutions

CUET Mathematics 2022 23 Aug Shift 1

Geometry

Medium

$\theta = \cos^{-1}\left(\frac{\sqrt{19}}{21}\right)$

$\theta = \cos^{-1}\left(\frac{\sqrt{19}}{\sqrt{21}}\right)$

$\theta = \cos^{-1}\left(\frac{19}{21}\right)$

$\theta = \cos^{-1}\left(\frac{9}{21}\right)$

✅ Correct Option: 3