For the Malthus model, use this link http://en.wikipedia.org/wiki/Malthusian_growth_model
For the Logistic model, use this link http://mathworld.wolfram.com/LogisticEquation.html
For the Malthus model, use this link http://en.wikipedia.org/wiki/Malthusian_growth_model
For the Logistic model, use this link http://mathworld.wolfram.com/LogisticEquation.html