Advertisements
Advertisements
प्रश्न
Find the sum of the following series
62 + 72 + 82 + ... + 212
उत्तर
62 + 72 + 82 + ... + 212
(12 + 22 + ... + 212) – (12 + 22 + ... + 52)
= `sum_1^21 "n"^2 - sum_1^5 "n"^2`
= `(("n"("n" + 1)(2"n" + 1))/6)_("n" = 21) - (("n"("n" + 1)(2"n" + 1))/6)_("n" = 5)`
= `((21 xx 22 xx 43)/6) - ((5 xx 6 xx 11)/6)`
= 3311 – 55
= 3256
APPEARS IN
संबंधित प्रश्न
Find the sum of the following series
1 + 2 + 3 + ... + 60
Find the sum of the following series
3 + 6 + 9 + ... + 96
Find the sum of the following series
1 + 4 + 9 + 16 + ... + 225
Find the sum of the following series
103 + 113 + 123 + ... + 203
Find the sum of the following series
1 + 3 + 5 + ... + 71
If 1 + 2 + 3 + ... + k = 325, then find 13 + 23 + 33 + ... + k3
If 13 + 23 + 33 + ... + k3 = 44100 then find 1 + 2 + 3 + ... + k
How many terms of the series 13 + 23 + 33 + … should be taken to get the sum 14400?
Rekha has 15 square colour papers of sizes 10 cm,11 cm,12 cm, …, 24 cm. How much area can be decorated with these colour papers?
The value of a motorcycle depreciates at a rate of 15% per year. What will be the value of the motorcycle for 3 year hence, which is now purchased for ₹ 45,000?
