Question

1+8x^3 [factorize]​

Answer 1

Given

1 + 8x³

Factorise it

Solution

Applying identity to solve this Factorise

a³ + b³ = (a + b)(a² - ab + b²)

= 1 + 8x³

= (1)³ + (2x)³

= (1 + 2x) [(1)² - 1×2x + (2x)²]

= (1 + 2x) [1 - 2x + 4x²]

Some important identities

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