Question
(22 + 42 + 62 + ... + 202) = ?
Answer: Option C
Was this answer helpful ?
(22 + 42 + 62 + ... + 202) = (1 x 2)2 + (2 x 2)2 + (2 x 3)2 + ... + (2 x 10)2
= (22 x 12) + (22 x 22) + (22 x 32) + ... + (22 x 102)
= 22 x [12 + 22 + 32 + ... + 102]
= `4 x 1/6 x 10 x 11 x 21`
= (4 x 5 x 77)
= 1540
Was this answer helpful ?
More Questions on This Topic :
Question 1.
13 + 23 + 33 + ... + 63 = ?
....
Question 3.
On multiplying a number by 7, the product ....
Question 7.
612
×
612....
Question 8.
397 x 397 + 104 x 104 + 2 x 397 x 104 = ?
....
Question 9.
-84 x 29 + 365 = ?
....
Submit Solution