Question

factorise (a^2-5a^2)^2-36
donot write unessesarily​

Answer 1

★ To factorise :

(a² - 5a²)² - 36

36 = 6²

We know that,

a² - b² = (a+b)(a-b)

(a² - 5a²)² - (6)²

{(a²-5a²) - 6} {(a² - 5a²) + 6}

= (a² - 5a² - 6)(a² - 5a² + 6)

= (-4a² - 6)(-4a² + 6)

= 2( -2a² - 3) × 2(-2a² + 3)

→ 4(- 2a² - 3)(- 2a² + 3)

★ Additional Information :

Important identities :

→ (a+b)² = a² + 2ab + b²

→ (a - b)² = a² - 2ab + b²

→ (a+b) (a - b) = a² - b²

→ (a + b)³ = a³ + b³ + 3ab(a+b)

→ (a - b)³ = a³ - b³ - 3ab(a - b)

→ a³ + b³ + c³ = 3abc , if a + b+ c = 0