From Förberedande kurs i matematik 2

Revision as of 08:04, 21 August 2008 (edit) Tekbot (Talk | contribs) m (Robot: Automated text replacement (-[[Bild: +[[Image:)) ← Previous diff		Current revision (14:47, 29 October 2008) (edit) (undo) Tek (Talk | contribs) m
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-	{{NAVCONTENT_START}}	+	When we remove the parentheses, the terms inside change sign,
-	<center> [[Image:3_1_1b.gif]] </center>	+
-	{{NAVCONTENT_STOP}}	+	{{Displayed math||<math>3i-(2-i)=3i-2+i\,\textrm{.}</math>}}
		+
		+	Then, we collect together real and imaginary parts,
		+
		+	{{Displayed math||<math>\begin{align}
		+	3i-2+i
		+	&=-2+(3i+i)\\[5pt]
		+	&=-2+(3+1)i\\[5pt]
		+	&=-2+4i\,\textrm{.}
		+	\end{align}</math>}}

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Current revision

When we remove the parentheses, the terms inside change sign,

\displaystyle 3i-(2-i)=3i-2+i\,\textrm{.}

Then, we collect together real and imaginary parts,

\displaystyle \begin{align} 3i-2+i &=-2+(3i+i)\\[5pt] &=-2+(3+1)i\\[5pt] &=-2+4i\,\textrm{.} \end{align}