Question

if x-y=5, xy=24 then find the value of x³- y³=​

Answer 1

Step-by-step explanation:

let a= x and b= y

by using identity (a^3-b^3= (a-b)^3 +3ab(a-b)

x^3-y^3 =(5)^3 +3×24(5)

x^3-y^3= 125+510

= 635

Answer 2

✯ Answer:

x³ - y³ = 485

✯ Step-by-step explanation:

Given:

• x - y = 5
• xy = 24

To find:

→ x³ - y³ = ?

Solution:

(x - y) = 5

Squaring on both sides,

   (x - y)² = 5²

➵ x² + y² - 2xy = 25

⇒ x² + y² - 2(24) = 25

⇒ x² + y² - 48 = 25

⇒ x² + y² = 25 + 48

⇒ x² + y² = 73

Now,

☞ x³ - y³ = (x - y) (x² + xy + y²)

➟ x³ - y³ = (x - y) (x² + y² + xy)

➥ x³ - y³ = (x - y) [(x² + y²) + xy]

↦ x³ - y³ = (5) (73 + 24)

⇢ x³ - y³ = 5 × 97

➪ x³ - y³ = 485

∴ x³ - y³ = 485