# what is the modulus of 1+i/1-i*1-i/1+i

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### 1 Answer

Simplifying the expression we get:

`(1+i)/(1-i)*(1-i)/(1+i)`

`=1`

The modulus or the absolute value of a complex number `z=a+bi` is `r=|z|=sqrt(a^2+b^2).`

If `z` is a real number i.e `b=0` , then `r=|a|` .

Here, `z=1+0*i` , so, `r=|1|=1`

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