
Area Enclosed by |ax| + |by| = c
The equation: \[ |ax| + |by| = c \] in 2‑D represents a rhombus centered at the origin.
From the equation:
These intercepts form the vertices of the rhombus.
If the intercepts are equal in magnitude, the rhombus becomes a square. In the given scenario, each diagonal measures: \[ d_1 = 4, \quad d_2 = 4 \]
The area of a rhombus is given by: \[ \text{Area} = \frac{1}{2} \times d_1 \times d_2 \] Substitute: \[ \text{Area} = \frac{1}{2} \times 4 \times 4 = 8 \]
\[ \boxed{8} \]
For any natural number $k$, let $a_k = 3^k$. The smallest natural number $m$ for which \[ (a_1)^1 \times (a_2)^2 \times \dots \times (a_{20})^{20} \;<\; a_{21} \times a_{22} \times \dots \times a_{20+m} \] is: