Math.pow vs. decimal exponents

Hello,

We’ve been trying to implement a calculation using a decimal exponent into Math.pow
Each time the exponent is a decimal and not strictly an integer, we get 1 as a result.

Current result is the following
Math.pow(2,2) gives 4
Math.pow(2,3) gives 8
Math.pow(2,3.5) gives 1

Did someone encounter this behaviour ?

Thanks for your help
Stéphane