Question

2×2+4×4+6×6 +...................+ 20×20 = ?
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Answer 1

Hello Friend

Here is your answer below,

= 2 × 2 + 4 × 4 + 6 × 6 + ........ + 20 × 20

= 2^2 + 4^2 + 6^2 + 8 ^2 + 10^2 + 12^2 + 14^2 + 16^2 + 18 ^2 + 20^2

= 4+16+36+64+100+144+196+256+324 +400

= 1540

I hope that helps you