Processing Math: Done

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Revision as of 15:43, 11 October 2010 (edit) Ian (Talk | contribs) ← Previous diff		Current revision (17:29, 27 March 2011) (edit) (undo) Ian (Talk | contribs)
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	& 5=20-\frac{k\times {{40}^{2}}}{5} \\		& 5=20-\frac{k\times {{40}^{2}}}{5} \\
	& \\		& \\
-	& 320k=15 \\	+	& 800k=15 \\
	& \\		& \\
-	& k=\frac{15}{320}=\frac{3}{64}	+	& k=\frac{15}{800}=\frac{3}{160}
	\end{align}</math>		\end{align}</math>
	Note that substituting for <math>k</math> and <math>c</math> in the expression for <math>v</math> we get		Note that substituting for <math>k</math> and <math>c</math> in the expression for <math>v</math> we get
-	<math>v=20-\frac{3{{t}^{2}}}{128}</math>	+	<math>v=20-\frac{3{{t}^{2}}}{320}</math>

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Current revision

v=adt=−ktdt=−2kt2+ct=0 v=20  c=20v=20−2kt2 Usingt=40 v=5gives5=20−5k402800k=15k=15800=3160

Note that substituting for k and c in the expression for v we get

v=20−3t2320