Find the value of for which the four points with position vectors and are coplanar.

Question

Philoid · Accepted Answer

Formula : -

andthen

(iii) Three vectors are coplanar if and only if

(iv) ifandthen,

Given: -

The four points are coplaner if vector AB⃗,AC⃗,AD⃗ are coplanar.

now, using

⇒ 4(50 – 25) – 6(15 + 20) + (λ + 1)(15 + 40) = 0.

⇒ λ = 1

hence the point are coplanar