It is known that lab-2l and lb-1l are opposite to each other. Try to find the formula It is known that la-2l and lb-1l are opposite to each other. Try to find the value AB (a + 1) (B + 1) (a + 2) (B + 2) (a + 2009) (B + 2009) of Formula 1 - + --- + --- +... + ---

It is known that lab-2l and lb-1l are opposite to each other. Try to find the formula It is known that la-2l and lb-1l are opposite to each other. Try to find the value AB (a + 1) (B + 1) (a + 2) (B + 2) (a + 2009) (B + 2009) of Formula 1 - + --- + --- +... + ---

Hello: la-2l + lb-1l = 0A = 2 b = 1 original formula = 1 / 1x2 + 1 / 2x3 + 1 / 3x4 +... + 1 / 2010x2011 = 1-1 / 2 + 1 / 2-1 / 3 + 1 / 3-1 / 4 +... + 1 / 2010-1 / 2011 = 1-1 / 2011 = 2010 / 2011 if you don't understand this question, please click "adopt as satisfactory answer" if you have other questions