Cube by Column method

For finding the cube by column method use the following formula:-
(a + b) 3 = a 3 + 3a 2 b + 3ab 2 + b 3
In this method, first find the 2 digits of a number.

Example:
1) 32 3 , so here the two digits are 3 and 2.
2) 46 3 , two digits are 4 and 6.

Examples:-

1) Find 24 3 .
Solution: Here two digits are 2 and 4.
a = 2, and b = 4. By using the column-method:-
Column I
Column II
Column III
Column IV
a3
3 x a2 x b
3 x a x b2
b3
23 = 8
+ 5
3 x 22 x 4 = 48
+ 10
3 x 2 x 42 = 96
+ 6
43 = 64
13
58
102
4
13
8
2
4

∴ 24 3 = 13824
_________________________________________________________________
2) Find 42 3 .
Solution: Here two digits are 4 and 2.
a = 4, and b = 2. By using the column-method:-

Column I
Column II
Column III
Column IV
a3
3 x a2 x b
3 x a x b2
b3
43 = 64
+ 10
3 x 42 x 2 = 96
+ 4
3 x 4 x 22 = 48
+ 0
23 = 8
74
100
48
8
74
0
8
8

∴ 42 3 = 74088


Cube - Cube Roots

• Cube of Numbers
• Perfect- Cube
• Properties of - Cube
• Cube by Column method
• Negative numbers-cube
• Cube - of Rational numbers
• Cube-Root
• Finding cube-root by Prime Factorization
• Cube-root of Rational numbers
• Estimating cube-root

From column method to Exponents

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