Find all zeroes of the function.

y = x^4 - 7x^2 + 12

To find the zeroes of the function, we set y to zero and solve for x:

0 = x^4 - 7x^2 + 12

Factoring the equation, we have:

0 = (x^2 - 3)(x^2 - 4)

Setting each factor equal to zero, we have two equations to solve:

x^2 - 3 = 0

x^2 - 4 = 0

Solving the first equation, we find:

x^2 = 3

Taking the square root of both sides, we have:

x = ±√3

Solving the second equation, we find:

x^2 = 4

Taking the square root of both sides, we have:

x = ±2

Therefore, the zeroes of the function are x = -2, -√3, √3, and 2.