prove-that-the-area-of-a-triangle-whose-two-sides-are-A-and-B-is-given-by-1-2-A-B-Also-find-the-direction-cosine-of-normal-to-this-area-Help-

Question Number 184656 by Mastermind last updated on 10/Jan/23

prove that the area of a triangle

whose two sides are \bar{A} and \bar{B} is

given by \frac{1}{2} ∣ A \times B ∣ .

Also find the direction - cosine

of normal to this area .

Help!

Answered by TheSupreme last updated on 10/Jan/23

∣ A \times B ∣=∣ a ∣∣ b ∣ s i n (θ)

Commented by TheSupreme last updated on 10/Jan/23

d i r e c t i o n n o r m a l

\hat{n} = \frac{A \times B}{∣ A \times B ∣}