CUBES AND CUBE ROOTS - Mathematics Form 2 Notes

Share via Whatsapp
{YouTube}GedbSagIN0M{/YouTube}


Cubes

  • The cube of a number is simply a number multiplied by itself three times e.g.
    × a × a=a3
    1 × 1 × 1 = 13; 8 = 2 × 2 × 2 = 23; 27 = 3 × 3 × 3 =33;

Example 1

What is the value of 63?

Solution
63 =6 x6 x 6
= 36 x 6
=216

Example 2

Find the cube of 1.4

Solution

=1.4 x 1.4 x 1.4
=1 .96 x 1 .4
=2.744



Use of Tables to Find Roots

  • The cubes can be read directly from the tables just like squares and square root.


Cube Roots Using Factor Methods

  • Cubes and cubes roots are opposite. The cube root of a number is the number that is multiplied by itself three times to get the given number

Example

The cube root of 64 is written as;

64 = 4 Because 4 x 4 x 4 =64
∛27 = 3 Because 3 x 3 x 3= 27

Example

Evaluate:∛216

Solution

=∛(2 x 2 x2 x 3 x3 x3 )
=2x3
=6

 

Note;

  • After grouping them into pairs of three you chose one number from the pair and multiply

Example

Find:
The volume of a cube is 1000 cm
3 .What is the length of the cube

Solution

Volume of the cube, v = l3
L3=1 000
L =
∛1000
=10
The length of the cube is therefore 10 cm

Join our whatsapp group for latest updates

Download CUBES AND CUBE ROOTS - Mathematics Form 2 Notes.


Tap Here to Download for 50/-




Why download?

  • ✔ To read offline at any time.
  • ✔ To Print at your convenience
  • ✔ Share Easily with Friends / Students


Read 9581 times Last modified on Monday, 17 January 2022 11:54
Get on WhatsApp Download as PDF
.
Subscribe now

access all the content at an affordable rate
or
Buy any individual paper or notes as a pdf via MPESA
and get it sent to you via WhatsApp

 

What does our community say about us?

Join our community on:

  • easyelimu app
  • Telegram
  • facebook page
  • twitter page
  • Pinterest