Giải thích các bước giải:
6x⁵ + 15x⁴ + 20x³ + 15x² + 6x + 1
= (6x⁵ + 3x⁴) + (12x⁴ + 6x³) + (14x³ + 7x²) + ( 8x² + 4x ) + (2x + 1)
= 3x⁴.(2x + 1) + 6x³.(2x + 1) + 7x².(2x + 1) + 4x.(2x + 1) + (2x + 1)
= (2x + 1)(3x⁴ + 6x³ + 7x² + 4x + 1)
= (2x + 1).[(3x⁴ + 3x³ + 3x²) + (3x³ + 3x² + 3x) + ( x² + x + 1)]
= (2x + 1) . [ 3x².(x² + x + 1) + 3x.(x² + x + 1) + (x² + x + 1)
= (2x + 1)(x² + x + 1)(3x² + 3x + 1)
