Cannot see a video solution to this problem, have no idea how this is to be solved? Can anybody help? GregMat - GregMat

I think you don’t need to solve this , Just eliminate the answers !

Option 1 : Is out because (1-1)^2+....+(10-1)^2 < (1^2+2^2+...+10^2) which is our first part of the question

Option 2 : is out because See : 10^2=100 is in our question while here we’re not squaring anything thus this terms will be less than what we’re looking for

Option 4: this is the first part of our question but we have additional part in +2 \times(1+2+...+10)+10, thus, You can also eliminate this

Option 5: According to BODMAS we need to solve for terms under the parenthesis than do the squaring, thus resulting term will be huge , hence,we eliminate this too! For eg: (1^2+2^2+3^2)<(1+2+3)^2 or (1+4+9=14)<(6^2=36)

Option 3 is the only remaining choice !

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