√(5+2√6)x+√(5−2√6)x=10
So I have squared both sides and got:
(5−2√6)x+(5+2√6)x+2√1x=100
(5−2√6)x+(5+2√6)x+2=100
I don't know what to do now
Answer
You don't have to square the equation in the first place.
Let y=√(5+2√6)x, then 1y=√(5−2√6)x. Hence you have y+1y=10 i.e. y2+1=10y i.e. y2−10y+1=0.
Hence, (y−5)2=24⇒y=5±2√6.
Hence, √(5+2√6)x=5±2√6⇒x=±2
(If you plug in x=±2, you will get 5+2√6+5−2√6 which is nothing but 10)
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