(7) Find the angles between the following lines (a) r = i– 2j + X(į – j) and r = 2i – 6j + µ(i – 2j); (b) r = i+2j + s(2i + j) and r = 4i +2j + t(7g – 2j). (8) If the direction vector of a line is 3i...

Extracted text: (7) Find the angles between the following lines (a) r = i– 2j + X(į – j) and r = 2i – 6j + µ(i – 2j); (b) r = i+2j + s(2i + j) and r = 4i +2j + t(7g – 2j). (8) If the direction vector of a line is 3i + 2j and the gradient of another line is -5/2, find the acute angle between the two lines. (9) Express the equations of the lines r · (i – j) + 7 = 0, r(i+ 3j) – 5 = 0 in parametric forms and hence find the position vector of their point of intersection. 1