I feel there is a problem somewhere...

[59, 7, 27, 67] and [3481, 49, 730, 4489]
Log for array2 square root :
[59, 7, 27, 67]

I have an error :
It should work with random inputs too: True should equal False

did I got the instruction wrong...

I see that you are very very new at CW, so:

• before posting issues look at the top of the page to see how many guys passed the kata (217 in Kotlin)
• if this number is big enough chances are that your code is wrong
• say which language you are using
• print the input to exactly see where your problem is

Otherwise you make everybody lose her time.

"expected:true but was:false" is not about the test you give but about another one.
Unfortunately your code is wrong! Sorry.

An issue is something wrong with the kata itself, like test cases, or not enough information on the description. Your code is wrong, probably, so if you want help, post your solution with three backticks before and after it and mark it with haveing spoiler content

There is no bug. "Expected: true, instead got: false" is for a previous test.