ABSTRACT
The polynomial https://www.w3.org/1998/Math/MathML"> f ( n ) = n 4 + 4 https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781003341468/d4c0c4c8-8291-444b-87ca-3efd613fe6ea/content/math2_1.tif" xmlns:xlink="https://www.w3.org/1999/xlink"/> does not look as if it has factors, but it does! Now here is the lateral bit: write https://www.w3.org/1998/Math/MathML"> n 4 + 4 https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781003341468/d4c0c4c8-8291-444b-87ca-3efd613fe6ea/content/math2_2.tif" xmlns:xlink="https://www.w3.org/1999/xlink"/> as https://www.w3.org/1998/Math/MathML"> n 4 + 4 n 2 + 4 − 4 n 2 = ( n 2 + 2 ) 2 − ( 2 n ) 2 = ( n 2 + 2 n + 2 ) ( n 2 − 2 n + 2 ) https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781003341468/d4c0c4c8-8291-444b-87ca-3efd613fe6ea/content/math2_3.tif" xmlns:xlink="https://www.w3.org/1999/xlink"/> .
