Name:
Anonymous
2009-09-12 22:38
Well, it doesn't look hard and I feel extremely retarded for not being able to figure it out but....HOW THE FUCK DO YOU SOLVE....
a^3 + (1/2)a = 9 ?!?!?!?!
Name:
Anonymous
2009-09-12 23:04
Solution of a cubic with no squared term:
If f = x^3 + px + q, then
x = \sqrt[3]{-\frac{q}{2}+\sqrt{\frac{q^{2}}{4}+\frac{p^{3}}{27}}}+\sqrt[3]{-\frac{q}{2}-\sqrt{\frac{q^{2}}{4}+\frac{p^{3}}{27}}}
Just plug in p=1/2 and q=-9.
http://en.wikipedia.org/wiki/Cubic_function#Cardano.27s_method