I want to obtain the result of:
3√√5+2−3√√5−2
Which turns out to be 1. Now, let's prettend we don't know what the result is. I solved it by stating
3√√5+2−3√√5−2=z
Then by cubing the equation:
4−3(3√√5+2−3√√5−2)=z3
z3+3z−4=0
Now, just by an inexplicable mysticism, the equation can be restated as:
(z−1)(z2+z+4)=0
Therefore, z=1, which is what I wanted to prove.
Are there another ways to solve this problem? I find this method quite impractical and not so elegant. I'm interested in ways to solve it that are MUCH simpler.
Thanks in advance!
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