Answer:
EVEN
Explanation:
the product of odd numbers is always odd
the product of even numbers is always even
the product of odd number and even one is always even
the sum of two odd numbers is always even
and the sum of two even numbers is always even
so if x is even number we have:
x²=x•x - even number
x⁴=x²•x² - even number
3x²=3•x² - even number
y = x⁴+3x² - even number
and if x is odd number we have:
x²=x•x - odd number
x⁴=x²•x² - odd number
3x²=3•x² - odd number
y = x⁴+3x² - even number