SOLUTION: Find the value of x that makes the following equation true: Equation: https://imgur.com/a/jiqbd9p

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Question 1150082: Find the value of x that makes the following equation true:
Equation: https://imgur.com/a/jiqbd9p

Found 2 solutions by ikleyn, jim_thompson5910:
Answer by ikleyn(52794) About Me  (Show Source):
You can put this solution on YOUR website!
.

Introduce new variable  t = sqrt%283x%29 + sqrt%283%2Fx%29.                            (1)


Notice that by its meaning  (1), t is a positive real number.    (*)


Your equation then takes the form


    %28t-2sqrt%283%29%29%2Ft = t%2F%28t%2Bsqrt%283%29%29.


Next cross-multiply


    %28t-2sqrt%283%29%29%2A%28t%2Bsqrt%283%29%29 = t%5E2

    t%5E2+-+%28sqrt%283%29%29%2At+-+6 = t%5E2

      t = - 6%2Fsqrt%283%29 = - 2%2Asqrt%283%29.    (2)


Now you see that t, expressed as (2), is a negative number.


It contradicts to the notice (*) above that t should be positive.


Hence, the original equation HAS NO SOLUTIONS.      A N S W E R






Plot y =  (left side, red), y =   (right side, green)

S O L V E D


Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

Problem


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The given equation

has the term sqrt%283x%29+%2B+sqrt%283%2Fx%29 show up a bunch of times as shown by the red marker



So we can replace every copy of sqrt%283x%29+%2B+sqrt%283%2Fx%29 with some other variable temporarily. Lets call that y.
Let y+=+sqrt%283x%29+%2B+sqrt%283%2Fx%29

The given equation

simplifies greatly to
%28y+-+2sqrt%283%29%29%2F%28y%29+=+%28y%29%2F%28y%2Bsqrt%283%29%29

Recall that the range of the square root function is nonnegative. In other words, it is impossible to get a negative value output from sqrt%28x%29. Adding two nonnegative square roots in y+=+sqrt%283x%29+%2B+sqrt%283%2Fx%29 like this means that y+%3E+0. We'll use this fact later.

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Let's solve for y

%28y+-+2sqrt%283%29%29%2F%28y%29+=+%28y%29%2F%28y%2Bsqrt%283%29%29

%28y+-+2sqrt%283%29%29%28y%2Bsqrt%283%29%29+=+y%2Ay Cross multiply

%28y+-+2sqrt%283%29%29%28y%2Bsqrt%283%29%29+=+y%5E2

A%28y%2Bsqrt%283%29%29+=+y%5E2 Temporarily, let A+=+%28y+-+2sqrt%283%29%29. This helps us distribute in the next step

A%2Ay+%2B+A%2Asqrt%283%29+=+y%5E2

y%2AA+%2B+sqrt%283%29%2AA+=+y%5E2

y%28y+-+2sqrt%283%29%29%2Bsqrt%283%29%28y+-+2sqrt%283%29%29+=+y%5E2 Replace A with %28y+-+2sqrt%283%29%29 again.

Distribute again

y%5E2+-+2y%2Asqrt%283%29+%2B+y%2Asqrt%283%29-6+=+y%5E2

y%5E2+-+y%2Asqrt%283%29-6+=+y%5E2

y%5E2+-+y%2Asqrt%283%29-6-y%5E2+=+y%5E2-y%5E2 Subtract y^2 from both sides

-y%2Asqrt%283%29-6+=+0

-y%2Asqrt%283%29-6%2By%2Asqrt%283%29+=+0%2By%2Asqrt%283%29 Add y*sqrt(3) to both sides

-6+=+y%2Asqrt%283%29

y%2Asqrt%283%29+=+-6

%28y%2Asqrt%283%29%29%2F%28sqrt%283%29%29+=+-6%2F%28sqrt%283%29%29 Divide both sides by sqrt(3)

y+=+-6%2F%28sqrt%283%29%29 Divide both sides by sqrt(3)

y+=+-3.46410161513776 we've run into a problem

The result we got y+=+-3.46410161513776 contradicts y+%3E+0

There are no solutions for y, which means that there are no solutions for x.