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Question
`3sqrt(x/5)+3sqrt(5/x)=10`
Solution
`3sqrt(x/5)+3sqrt(5/x)=10`
Let `sqrt(x/5)=y`
`Then 3y+3/y=10`
⇒ `(3y^2+3)/y=10`
⇒ `3y^2+3=10y`
⇒ `3y^2-10y+3=0`
⇒` 3y^2-9y-y+3=0`
⇒ `3y(y-3)-1(y-3)=0`
⇒` (y-3)-1(y-3)=0`
If y – 3 = 0 Or 3y – 1 = 0
Then y = 3 Or y =`1/3`
`sqrt(x/5)=3 or sqrt(x/5)=1/3`
`⟹ x/5=9 or x/5=1/9`
⟹`x=45 or 9x =5`
⟹ x=45 or x=`5/9`
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