Question

Factorise:
1. x2 + z2 - 2xz​

Answer 1

Given

Factorise:

1. x2 + z2 - 2xz

Solution

→ x² + z² - 2xz

★ Applying identity :

(a - b)² = a² + b² - 2ab

→ (x)² + (z)² - 2*x*z

→ (x - z)²

→ (x - z)(x - z)

Some identities

• (a + b)² = a² + b² + 2ab
• (a + b)³ = a³ + b³ + 3ab(a + b)
• (a - b)³ = a³ - b³ - 3ab(a - b)
• a² - b² = (a + b)(a - b)