Question

factorise 8y^3-125z^3
its urgent​

Answer 1

GIVEn

8y³ - 125z³

Factories it

SOLUTIOn

→ 8y³ - 125z³

Applying identity :

a³ - b³ = (a - b)(a² + ab + b²)

→ (2y)³ - (5z)³

→ (2y - 5z)[(2y)² + 2y*5z + (5z)²]

→ (2y - 5z)[4y² + 10yz + 25z²]

SOMe IDENTITIEs

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

Answer 2

(2y)^3 - (5z)^3

a^3 - b^3 =(a-b) (a^2+2ab+b^2)

(2y)^3 -(5z)^3 = (2y -5z) (2y^2 +2(2y) (5z) +5z^2)

= (2y -5z) (4y^2+20yz +25z^2)