it is a result in most of the iit books that |z|² = |z²|

sustituting z=i

LHS= |i|² = i² = -1

RHS= |i²| = |-1| = 1

why is this problem occuring though the result is used in many books ?

DEar Raghunath

you have written

LHS= |i|² = i² = -1

this is a mod you can't open mod in this way

correct way is

      |i|²    = |0+i|²

                 =√(0²+1²)

                 =1

but you open mod as a simple bracket which is wrong.

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