6. For two numbers $a, b$, a new operation is defined as $a \triangle b=3 \times a+2 \times b, a \nabla b=2 \times a+3 \times b$. Therefore, $2 \triangle(3 \nabla 4)$ $=$ $\qquad$
【Answer】 42
【Analysis】 $3 \nabla 4=2 \times 3+3 \times 4=18,2 \triangle(3 \nabla 4)=2 \triangle 18=3 \times 2+2 \times 18=42$