## 17Calculus Precalculus - Adding and Subtracting Complex Numbers

##### 17Calculus

Adding and Subtracting Complex Numbers

Adding, subtracting, multiplying and dividing using complex numbers work exactly like radicals. For example, to simplify $$(1+3\sqrt{2}) + (6+8\sqrt{2})$$, you would combine the parts without the radicals and then combine the parts with the radicals. So the result is $$(1+3\sqrt{2}) + (6+8\sqrt{2}) = (1+6) + (3+8)\sqrt{2} = 7+11\sqrt{2}$$.

With complex numbers, $$(1+3i) + (6+8i) = (1+6) + (3+8)i = 7+11i$$. [ Remember: $$i=\sqrt{-1}$$ ]
Subtraction works just as you would expect. Insteading adding the individual terms, you subtract the second one from the first.

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