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If x=sum(n=0)^ooa^n , y=sum(n=0)^oob^n ,...

If `x=sum_(n=0)^ooa^n , y=sum_(n=0)^oob^n , z=sum_(n=0)^ooc^n , w h e r e ra ,b ,a n dc` are in A.P. and `|a|<,|b|<1,a n d|c|<1,` then prove that `x ,ya n dz` are in H.P.

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CENGAGE PUBLICATION-SEQUENCES AND SERIES-All Questions
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  2. Find the sum sum(r=1)^n1/((a r+b)(a r+a+b))dot

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  3. If x=sum(n=0)^ooa^n , y=sum(n=0)^oob^n , z=sum(n=0)^ooc^n , w h e r e ...

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  5. Find the sum of the series sum(k=1)^(360)(1/(ksqrt(k+1)+(k+1)sqrt(k)))

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  7. Find the value of 11^2+12^2+13^2++20^2dot

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