The number of values of a for which (a2−3a+2)x2+(a2−5a+6)x+a2−4=0 is an identity in x is

The number of values of a for which (a2−3a+2)x2+(a2−5a+6)x+a2−4

1.	The number of values of a for which (a2−3a+2)x2+(a2−5a+6)x+a2−4=0 is an identity in x is
Answer» The number of values of a for which $(a^{2} - 3 a + 2) x^{2} + (a^{2} - 5 a + 6) x + a^{2} - 4 = 0$ is an identity in x is