Question

a/b = 7/3, now find the value of (a³-b³) / b³

Answer 1

Step-by-step explanation:

✑ ɢɪᴠᴇɴ :-

A + B = 5

AB = 3

✑ ᴛᴏ ғɪɴᴅ :-

A³ + B³ = ?

✑ sᴏʟᴜᴛɪᴏɴ :-

We know that,

➢ (A + B) ³ = A³ + B³ + 3AB(A + B)

So,

Put the above given values in it, we get

→ (5)³ = A³ + B³ + 3×3(5)

→ 125 = A³ + B³ + 45

→ A³ + B³ = 125 - 45 = 80

Hence,

➥ A³ + B³ = 80

➲ More Identities :-

( a + b) ² = a² + b² + 2ab

( a - b) ² = a² + b² - 2ab

(a + b) (a - b) = a² - b²

( a + b) ³ = a³ + b³ + 3ab ( a + b)

( a - b) ³ = a³ - b³ - 3ab (a - b)