Answer:x = +- 2 and x = +- √2
Step-by-step explanation:
Let's covert x^4 - 6x^2 + 8 = 0 into quadratic equation.
Let e = x ^ 2
So,
(x^2)^2 - 6x^2 + 8 = 0
e^2 - 6e + 8 = 0
e^2 - 4e - 2e + 8 = 0
e( e - 4 ) -2( e - 4 )
( e - 4 ) ( e - 2 ) = 0
Either,
e - 4 = 0
x^2 - 4 = 0 ( REMEMBER THAT e= x^2)
x^2 = 4
x = +- 2
Or,
e - 2 = 0
x^2 = 2
x = +- √2
