Question

( frac{1}{(1+a)(2+a)}+frac{1}{(2+a)(3+a)}+frac{1}{(3+a)(4+a)}+cdots )
( Rightarrow frac{(2+a)-(1+a)}{(1+a)(2+a)}+frac{(3+a)-(2+a)}{(2+a)(3+a)}+cdots )
( frac{1}{1+a}-frac{1}{2+a}+frac{1}{2+a}+frac{1}{3+a}+frac{1}{3+a}-frac{1}{4+a}+1-cdots-1 )
( =frac{1}{1+a} )

# 1 + 1 + ...upto o is (2 + a)(3+ a) (3 + a)(4 + a) 3008 1 9. The value of (1+ a)(2+a) (where, a is constant) (a) (b) Tra Data (d) None of these Mouch that f/1) =

Solution