Self-test 5I.3A

[Danielle_Cho_3A]

Hello,
I was trying to solve Self-test 5I.3A, but I got stuck after the RICE table because K is not less than 10^(-3) so we can't use the approximation method and disregard X. However, we are stuck with a X^4 expression to solve, and we don't have anything like the quadratic formula to solve this. How can we solve this problem?

[Isabella Torriani 2L]

I guess the only way would be to expand the binomial cube out using (a + b)^3 = a3 + 3a^2b + 3ab^2 + b3, but that's super long and tedious. I don't think we have to worry about doing anything beyond the quadratic formula for the midterm though because he told us that anything that would result in a cubic equation would have a low K val.