1) k³ + t³ = (k + t)(k² - kt + t²)
2) 8 - x³ = 2³ - x³ = (2 - x)(4 + 2x + x²)
3) c³ + d³ = (c + d)(c² - cd + d²)
4) 64 - y³ = 4³ - y³ = (4 - y)(16 + 4y + y²)
