If `vec(a) = hat(i) + hat(j) + 2 hat(k)` and `vec(b) = 3 hat(i) + 2 hat(j) - hat(k)`, find the value of`(vec(a) + 3 vec(b))`. `( 2 vec(a) - vec(b))`.

Explanation

(a) T - mg = ma
(b) `T_(x) +F_(x) = A_(x) +B_(x)`
(c) `T_(x) - F_(x) = A_(x) - B_(x)`
(d) T + mg = ma