Factorize the question given below:

Question

21x²-2x+1/21

Answer 1

It is a tricky question.

21x²-2x+1/21

=1/21(21²x²-42x+1)

=1/21[(21x)²-2(21x)1+1²] .................. difference of two quantities squared formula

=1/21(21x-1)²

Answer 2

21x² - 2x + 1/21

 

(1/21)(21²x² - 42x + 1)

 

Need two numbers that multiply to give 21² and add to give -42.  Answer -21 and -21:

 

(1/21)(21²x² - 21x - 21x + 1)

 

(1/21)(21x(21x-1) - (21x-1))

 

(1/21)(21x - 1)²