The value of (a - b)(a + b) + (b - c)(b + c) + (c - a)(c + a) is:
Show answer & explanation
Correct answer: C
Explanation
(a − b)(a + b) + (b − c)(b + c) + (c − a)(c + a)
According to the formula:
(a − b)(a + b) = a² − b²
= (a² − b²) + (b² − c²) + (c² − a²)
= a² − b² + b² − c² + c² − a²
= 0