• Call Us : 03082533000 (WhatsApp)
  • Email Us : TestPointpk.com@gmail.com
Sticky Note
If x + 1/x = 3, then what is the value of x³ + 1/x³?
  1. 18
  2. 20
  3. 21
  4. None of these
Explanation

Given x + 1/x = 3

To find x³ + 1/x³:

(x + 1/x)³ = x³ + 3(x²)(1/x) + 3(x)(1/x)² + 1/x³

= x³ + 3x + 3/x + 1/x³

= x³ + 1/x³ + 3(x + 1/x)

(x + 1/x)³ = x³ + 1/x³ + 3(3)

27 = x³ + 1/x³ + 9

x³ + 1/x³ = 27 - 9

= 18

Related MCQs

  1. 11
  2. 12
  3. 13
  4. None of these
اس سوال کو وضاحت کے ساتھ پڑھیں

  1. 2/x + 12/(x +5)
  2. 3/x + 22/(x +5)
  3. 4/x + 16/(x +5)
  4. None of these
اس سوال کو وضاحت کے ساتھ پڑھیں

  1. 14
  2. 15
  3. 16
  4. None of these
اس سوال کو وضاحت کے ساتھ پڑھیں

  1. 4
  2. 5
  3. 6
  4. None of these
اس سوال کو وضاحت کے ساتھ پڑھیں

  1. 43/3
  2. 3/43
  3. 43/43
  4. None of these
اس سوال کو وضاحت کے ساتھ پڑھیں

Leave a Reply

Your email address will not be published. Required fields are marked *

1 + 2 = ?



All Rights Reserved © TestPointpk.com