Quantitative Aptitude • Algebra
(a-b)² Formula
basic Level
Formula
(a-b)² = a² - 2ab + b²
Explanation
The square of difference of two numbers equals the sum of their squares minus twice their product.
Example
(5-3)² = 25 - 30 + 9 = 4
Quick Trick & Mnemonic
MNEMONIC: 'Minus in middle' - Same as (a+b)² but the 2ab term is negative.