1.
If a⃗×b⃗×c⃗=0\vec{a} \times \vec{b} \times \vec{c} = 0, a⃗×b⃗+b⃗×c⃗+c⃗×a⃗=6(b⃗×c⃗)\vec{a} \times \vec{b} + \vec{b} \times \vec{c} + \vec{c} \times \vec{a} = 6(\vec{b} \times \vec{c}), then the locus of the point (x,y)(x, y) is