What values of xxx must be excluded from the domain of dfrac20(x−21)(x+22)\\dfrac{20}{(x - 21)(x + 22)}dfrac20(x−21)(x+22)?
x=0x = 0x=0
x=21x = 21x=21 and x=−22x = -22x=−22
x=21x = 21x=21 only
x=−21x = -21x=−21 and x=22x = 22x=22