Expand the left-hand side of the given equation: \[ (A + B)^2 = A^2 + AB + BA + B^2. \]
Equating both sides: \[ A^2 + AB + BA + B^2 = A^2 + B^2. \]
Cancel \( A^2 \) and \( B^2 \): \[ AB + BA = 0. \]
Rearranging: \[ AB = -BA. \]
Therefore, the correct answer is (B) \( AB = -BA \).
On the basis of the following hypothetical data, calculate the percentage change in Real Gross Domestic Product (GDP) in the year 2022 – 23, using 2020 – 21 as the base year.
Year | Nominal GDP | Nominal GDP (Adjusted to Base Year Price) |
2020–21 | 3,000 | 5,000 |
2022–23 | 4,000 | 6,000 |