An angle between the lines whose direction number are 1, -2, 1 and -6, -1, 4 is

The measure of acute angle between the lines whose direction ratios are 3, 2, 6 and -2, -1, 2 is

The acute angle between the lines whose direction ratios are 3, 2, 6 and -2, 1, 2 is

The acute angle between the lines whose direction ratios are 1, 2, 2 and -3, 6, -2 is

The acute angle between the straight lines whose direction numbers are 1, 1, 2 and (sqrt(3)-1),(-sqrt(3),-1), 4 is -

Find angle between the two lines whose direction ratios are 1,-2,1 and 4,3,2 respectively

Find the angle between the lines whose direction ratios are 2, 1, -2 and 3, -4, 5.

Find the acute angle between two straight lines whose direction number are -4, 3, 5 and 3, 4, 5.

The direction cosines of the lines bisecting the angle between the line whose direction cosines are l_1, m_1, n_1 and l_2, m_2, n_2 and the angle between these lines is theta , are