Answer
$2+11i$
Work Step by Step
Step 1: $(2+i)^{3}$
Step 2: $(2+i)(2+i)(2+i)$
Step 3: $(2+i)(2(2+i)+i(2+i))$
Step 4: $(2+i)(4+2i+2i+i^{2})$
Step 5: $(2+i)(4+4i+i^{2})$
Step 6: $(2+i)(4+4i-1)$
Step 7: $(2+i)(3+4i)$
Step 8: $2(3+4i)+i(3+4i)$
Step 9: $6+8i+3i+4i^{2}$
Step 10: $6+11i-4$
Step 11: $2+11i$
