Question

Expand : (k+4)³=_____ *
2 points
k³+12k²+48k+64
k³-12k²-48k+64
k³-12k²-48k-64
k³-12k²+48k+64

Answer 1

${k}^{3} + {12k}^{2} + 48k + 64.$

Step-by-step explanation:

(k+ 4)³ = (k + 4)(k + 4)(k + 4).

= [(k + 4)(k + 4)](k +4).

= [k² + k4 + 4k + 4²](k + 4).

= [k² + 2k4 + 4²](k + 4).

= k³+ 2k²(4) + k(4²) + k²(4) + 2k(4²) + 4³.

= k³ + 3k²(4) + 3k(4²) + 4³.

= k³ + 12k² + 48k + 64.