Find the minimum root of
x 2 − 1 x 3 + 1 = x + 2 x 6
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But just I was wondering that this doesn't work. try plugging in values. And for some reasons, it doesn't work and it has to be just a root which came with the quadratic, nothing else. The answer has to be 1 . 5
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You're right. It's because we squared it, and so an extra root was created.
Plugging in values would have made it work only if we took the negative value of the underroot of 6/x. This problem was indeed caused due to squaring.
Please fix this.
I graphed the function given as it was , the graph is given below :
The graph tends to infinity as x tends to 0 , I am telling this since it is not visible from the graph , but you can very well see that x=1 is the asymptote and x= 1.5 is it's least root .
Again proving Kartik's point
@siddharth bhatt , @shubhendra singh
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If x = 1, then LHS is not defined..and clearly LHS not equal to RHS ;)
Oh ! I just didn't checked the value......sorry guys thanks for correcting me.
Please anyone change the answer to 1.5
2/3 is invalid solution, given the form of the equation . (35/27)/(-5/9) = 2/3 +sqrt(9), which is invalid
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Given expression can be written as
( x + 1 ) ( x − 1 ) ( x + 1 ) ( x 2 + 1 − x ) = x − 1 x 2 + 1 − x = x + x − 1 1 = x + x 6
So x − 1 1 = x 6
⇒ x − 1 = 6 x
Whole square and re-arrange to get x 2 − 6 1 3 x + 1 = 0
= ( x − 2 3 ) ( x − 3 2 )
But x = 3 2 does not satisfy the equation.
So the answer should be 2 3