Expressing as a product of prime factors
Given the following numbers list down the prime numbers.
1, 2, 20, 5, 23, 0.1, 7, 4, 29, 13, 32
From the given list above, the prime number are 2, 5, 7, 13, 23, 29
We consider the number 36
The number 36 can be expressed as a product of prime factors
using a tree diagram shown below:
The number 2 and 3 are the prime factors of 36 hence 36 = 2 x 2 x 3 x 3
2 x 2 can be written as 22 in short form. Similarly, 3 x 3 can be written as 32
Therefore 36 = 22 x 32
The number 2 in 22 is called a power. It shows the number of times the number
has been multiplied by itself.
Similarly the number 2 in 32 is also called a power.
22 is read as "two to power two" and 32 is read as "three to power two".
When we write 36 = 22 x 32, we say that 36 has been expressed as a product
of prime factor in power form.
Worked out Examples
Express each of the following numbers as a product of its prime factors.
1. 32
2. 72
3. 54
4. 225