If [x] be the greatest integer less than or equal to x,
then $\sum\limits_{n = 8}^{100} {\left[ {{{{{( - 1)}^n}n} \over 2}} \right]}$ is equal to :
Solution
$\sum\limits_{n = 8}^{100} {\left[ {{{{{( - 1)}^n}n} \over 2}} \right]}$<br><br>= [4] + [-4.5] + [5] + [-5.5] + [6] +..... + [-49.5] + [50]
<br><br>= 4 - 5 + 5 - 6 + 6 ......-50 + 50
<br><br> = 4
About this question
Subject: Mathematics · Chapter: Complex Numbers and Quadratic Equations · Topic: Quadratic Equations
This question is part of PrepWiser's free JEE Main question bank. 223 more solved questions on Complex Numbers and Quadratic Equations are available — start with the harder ones if your accuracy is >70%.