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Adding complex numbers

To add complex numbers, you simply add together the real parts and add together the imaginary parts separately.

Let z=a+biz=a+bi and let w=c+diw=c+di.
z+w=(a+c)+(b+d)iz+w=(a+c)+(b+d)i

Examples of adding complex numbers​

Add the complex numbers 5+4i5+4i and 6−2i6-2i​

  • 5+6=115+6=11
  • (4+−2)i=2i(4+-2)i=2i
  • Answer: 11+2i11+2i

Add the complex numbers −3i−4-3i-4 and 5+i5+i​

  • −4+5=1-4+5=1
  • (−3+1)i=−2i(-3+1)i=-2i
  • Answer: 1−2i1-2i