Let A(2, 3, 5) and C(–3, 4, –2) be opposite vertices of a parallelogram ABCD. If the diagonal BD→=i^+2j^+3k^, then the area of the parallelogram is equal to [2024]
(2)
Area of parallelogram ABCD
=12|AC→×BD→|
=12|(–5i^+j^–7j^)×(i^+2j^+3k^)|
=12||i^j^k^–51–7123||
=12|(3+14)i^–(-15+7)j^+(–10–1)k^|
=12|(17i^+8j^–11k^)|
=12289+64+121=12474 sq. units.