Integral part of the product of non-real roots of equation x4−4x3+6x2−4x=69 is _________.
We have x4−4x3+6x2−4x=69
⇒ x4−4x3+6x2−4x+1=70⇒ (x−1)4=70⇒ (x−1)2=±70
For the product of non-real roots, consider
(x−1)2=−70⇒ x2−2x+1+70=0
Therefore, product is 1+70, whose integral part is 9.