Solution 3.2:4b

From Förberedande kurs i matematik 2

Revision as of 15:25, 22 October 2008 by Ian (Talk | contribs)
Jump to: navigation, search

We calculate what the expression will be


\displaystyle \left( 2-i \right)+\left( 5+3i \right)=2+5+\left( -1+3 \right)i=7+2i

and then take the magnitude:


\displaystyle \left| 7+2i \right|=\sqrt{7^{2}+2^{2}}=\sqrt{49+4}=\sqrt{53}


NOTE: Note that it is not possible to take the magnitude of the terms individually


\displaystyle \left| \left( 2-i \right)+\left( 5+3i \right) \right|\ne \left| 2-i \right|+\left| 5+3i \right|