Algebra of complex numbers (advanced)
General · Mathematics
Study notes
Q: Compute (2+3i)(1-i) and 1/(1+i). (2+3i)(1-i) = 2-2i+3i-3i² = 2+i+3 = 5+i. 1/(1+i): multiply (1-i)/(1-i): (1-i)/2 = 1/2 - i/2. Check: (1+i)(1/2-i/2) = 1/2-i/2+i/2-i²/2 = 1/2+1/2 = 1 ✓!