Question

If ` vec(AB) = vecb and vec(AC) =vecc` then the length of the perpendicular from A to the line BC is
A. `(|vecb xx vecc|)/(|vecb + vecc|)`
B. ` (|vecb xx vecc|)/(| vecb -vecc|) `
C. ` (| vecb xx vecc|)/(2 |vecb -vecc|)`
D. ` (|vecb xx vecc|)/( 2|vecb + vecc|) `

Answer 1

Correct Answer - B
we have,
Area of ` triangleABC = 1/2|vec(AB) xx vec(AC)|= 1/2 |vecb xx vecc|`
Also,
Area of ` triangleABC = 1/2 { vec(BC) | xx " Length of the " bot " from A and BC " }`
Required length = ` (|}vecb xx vecc|)/(|vec(BC)| = (|vecb xx vecc|)/ (|vecb - vecc|)`