Qual é a fatoração primária de 180?

We have to obtain the factors of 180 which are #color(blue)"prime numbers"#

A#color(blue)" prime number"# being a number with only 2 factors.That is 1 and the number itself.

For example #"5 only has 2 factors 1 and 5"rArr5=1xx5#

Here are the first few #color(blue)"prime numbers"#

#2,3,5,7,11,13,.....#

A number which is not prime is a #color(red)"composite number".# Composite numbers have more than 2 factors. All composite numbers can be expressed as a product of prime factors.

For example 10 has factors 1 ,2 ,5 and 10 but can be expressed as a product of prime factors.

#rArr10=2xx5#

Existem várias maneiras de encontrar os principais fatores de um número. Aqui está um.

Starting with 180, divide it by the lowest prime number 2 , repeat until it cannot be divided by 2 and move on to next prime number 3 and so on. When the remainder is 1 stop-we have obtained our prime factors.

#•180÷color(red)(2)=90#

#•90÷color(red)(2)=45 " which cannot be divided by" 2to3#

#•45÷color(red)(3)=15#

#•15÷color(red)(3)=5" which cannot be divided by" 3to5#

#•5÷color(red)(5)=1" having reached 1, we are there"#

#rArr180=color(red)(2xx2xx3xx3xx5)=2^2xx3^2xx5#