A) 942
B) 892
C) 946
D) 960
Correct Answer: C
Solution :
\[1.1+2.3+3.5+4.7+...\]upto 11 terms |
\[=\sum\limits_{r=1}^{11}{r.(2r-1)}\] |
\[=2\sum\limits_{r=1}^{11}{{{r}^{2}}}-\sum\limits_{r=1}^{11}{r}\] |
\[=\frac{2.(11)(12)(23)}{6}-\frac{11(12)}{2}\] |
\[=44(23)-11(6)=946.\] |
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