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If (1+i)(1+2i)(1+3i)........(1+n i)=a+i ...

If `(1+i)(1+2i)(1+3i)........(1+n i)=a+i b ,t h e n2xx5xx10 ....(1+n^2)` is equal to `sqrt(a^2+b^2)` (b) `sqrt(a^2-b^2)` (c) `a^2+b^2` (d) `a^2-b^2` (e) `a+b`

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Verified by Experts

The correct option is `C`

`a^2+b^2`

We have

`(1+i)(1+2i)(1+3i).......(1+ni)=a+ib`.........(i) ...
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