English

Find the Cube of : ( 3a - 1/A ) (A ≠ 0 ) - Mathematics

Advertisements
Advertisements

Question

Find the cube of : `( 3a - 1/a )  (a ≠ 0 )`

Sum

Solution

( a - b )3 = a3 - 3a2b + 3ab2 - b3

`( 3a - 1/a )^3`

= `(3a)^3 - 3 × (3a)^2 × 1/a + 3. 3a (1/a)^2 - (1/a)^3`

= `27a^3 - 3 . 9a^2. 1/a + 9a. 1/a^2 - 1/a^3`

= `27a^3 - 27a + 9/a - 1/a^3`.

shaalaa.com
  Is there an error in this question or solution?
Chapter 4: Expansions (Including Substitution) - Exercise 4 (B) [Page 60]

APPEARS IN

Selina Concise Mathematics [English] Class 9 ICSE
Chapter 4 Expansions (Including Substitution)
Exercise 4 (B) | Q 1.4 | Page 60
Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×