(10y^3 -x) (10y^3 +x)

Question

How to get from 100y^6 - x

to

(10^3-x) (10^3 +x)

Answer 1

100y^6 - x^2  to get the answer that you show the x must be squared...

10^2 (y^3)^2 - x^2 factor

(10y^3 - x) (10y^3 + x) no middle term it cancels out

 

 

 

Answer 2

Thanks, that means the text book is wrong.  My guess is it should have read         100y^6 - x^2, but what I sent was the question and answer in the back of the text.

Answer 3

(10y^3 - x)(10y^3 + x) = (10y^3)^2 - x^2

                                      = 100y^6 - x^2