The sum of n terms of the following series 1+(1+ x )+ [1+ x + x ^ 2 )+ . will be
Mathematics · JEE Main · NTA Exams — Progression and Series
The sum of n terms of the following series \(1+(1+\mathbf{x})+\left[1+\mathbf{x}+\mathbf{x}^{2}\right)+\ldots .\)will be
- \(\frac{1-\mathbf{x}^{n}}{1-\mathbf{x}}\)
- \(\frac{\mathbf{x}\left(1-\mathbf{x}^{7}\right)}{1-\mathbf{x}}\)
- \(\frac{n(1-x)-x\left(1-x^{n}\right)}{(1-x)^{2}}\)
- None of the above
Answer
(C) n(1-x)-x (1-x^ n ) (1-x)^ 2
Sign up free on Edukali to view the step-by-step worked solution and practice thousands of similar questions.
Related practice questions
- Find the sum of first 24 terms of an AP a 1 , a 2 , a 3 ....., if it is known that a 1 + a 5 + a 10 + a 15 +…
- If a_ 1 , a_ 2 , a_ 3 a_ n be an AP of non-zero terms then 1 a_ 1 a_ 2 + 1 a_ 2 a_ 3 + + 1 a_ n-1 a_ n is
- If a_ k a_ k-1 +a_ k-1 a_ k-2 =2 a_ k a_ k-2 , k 3 and here S_ p = _ k=1 ^ p 1 a_ k and given that S_ 2 p S_…
- If a _ 1 , a _ 2 , a _ 3 ( a _ 1 >0 ) are three successive terms of a G.P. with common ratio r, the value of…
- The sum of first ten terms of an AP is four times the sum of its first five terms, then ratio of first term…
- Let, f(1)=1 and f(n)=2 _ r=1 ^ n-1 f(r) . Then, _ n=1 ^ m f(n) is equal to
- The n th term of a GP is 128 and the sum of its n terms is 255. If its common ratio is 2 then its first term…
- If α and β are the roots of the equation 375 x 2 - 25x - 2 = 0, then _ n r=1 _ n r=1 ^ n ^ r + _ n _ n ^ n ^…
More Progression and Series questions · Browse all practice questions