zeros are the x values that make the expression or function equal to zero. Three things are being multiplied together (each in a parenthesis). Anything multiplied by zero will make the expression equal zero.
when x = 0 , f(x) = 0
when (x^2 - 6) = 0 , f(x) = 0
x^2 = 6
x = sqrt(6)
when (3x+2) = 0 , f(x) = 0
3x = -2
x = -2/3
then the zeros are: 0, sqrt(6) and -2/3
