Solution 2.1:3f
From Förberedande kurs i matematik 1
Treating \displaystyle 4x as one term, we can write
| \displaystyle \qquad 16x^2+8x+1=(4x)^2 +2\cdot 4x +1 |
and since \displaystyle y^2 +2y+1=(y+1)^2 we obtain
| \displaystyle \qquad (4x)^2 +2\cdot 4x +1= (4x+1)^2 . |
