Observe the following statements:
Assertion (A) : If vertices of a triangle are `A(vec(a)), B(vec(b)), C(vec(c ))`, then length of altitude through A is `(|vec(a) xx vec(b) + vec(b) xx vec(c)+ vec(c ) xx vec(a)|)/(|vec(b)-vec(c )|)`
Reason (R ): Area of triangle is `Delta = (1)/(2)` (Base) (Height) `= (1)/(2) |vec(AB) xx vec(AC)|`

Options

A. A, R are true, `R rArr A`
B. A, R are true `R cancel(rArr) A`
C. A is false, R is true
D. A is true, R is false

Answer

A