Solve for x in the given equation \(\dfrac{\sqrt{x}}{\sqrt{3}x+\sqrt{2}} = \dfrac{1}{2\sqrt{6}x+4}\) .
sqrt(x) / [ sqrt(3)*x + sqrt(2) ] = 1 / [ 2*sqrt(6)*x + 4]
sqrt(x) / [ sqrt(3)*x + sqrt(2) ] = 1 / [(2(*sqrt(6)*x + 2) ] multiply both sides by 2
2sqrt (x) / [sqrt(3)*x + sqrt(2)] = 1 / [ sqrt(6)*x + 2] cross multiply
(2sqrt (x)) [ sqrt(6)*x + 2] = sqrt(3)*x + sqrt(2)
Factor sqrt (2) out of sqrt sqrt(6)*x + 2
[2sqrt (x) ] ( [sqrt (2)] * [sqrt(3) *x + sqrt(2)] ) = [ sqrt (3)*x + sqrt(2) ]
2sqrt(2)* sqrt(x) [ sqrt (3)*x + sqrt(2)] = [sqrt(3)*x + sqrt(2)]
2sqrt(2)*sqrt(x) [ sqrt (3)*x + sqrt(2)] - [sqrt(3)*x + sqrt(2)] = 0
[ sqrt (3)*x + sqrt(2)] [ 2sqrt(2)* sqrt(x) - 1 ] = 0
Set both factors to 0 and either
sqrt (3) * x + sqrt (2) = 0 → x = -sqrt (2)/ sqrt(3)
But this gives a non-real result to the original problem
Or
2sqrt(2) * sqrt(x) - 1 = 0
sqrt(8) * sqrt (x) = 1
sqrt (8x) = 1 square both sides
8x = 1 divide both sides by 8
x = 1/8
Solve for x:
x/(3 x^2 + 2) = 1/(24 x^2 + 16)
Cross multiply:
x (24 x^2 + 16) = 3 x^2 + 2
Expand out terms of the left hand side:
24 x^3 + 16 x = 3 x^2 + 2
Subtract 3 x^2 + 2 from both sides:
24 x^3 - 3 x^2 + 16 x - 2 = 0
The left hand side factors into a product with two terms:
(8 x - 1) (3 x^2 + 2) = 0
Split into two equations:
8 x - 1 = 0 or 3 x^2 + 2 = 0
Add 1 to both sides:
8 x = 1 or 3 x^2 + 2 = 0
Divide both sides by 8:
x = 1/8 or 3 x^2 + 2 = 0
Subtract 2 from both sides:
x = 1/8 or 3 x^2 = -2
Divide both sides by 3:
x = 1/8 or x^2 = -2/3
Take the square root of both sides:
x = 1/8 or x = i sqrt(2/3) or x = -i sqrt(2/3)
x/(3 x^2 + 2) ⇒ 1/(8 (2 + 3 (1/8)^2)) = 8/131
1/(24 x^2 + 16) ⇒ 1/(16 + 24 (1/8)^2) = 8/131:
So this solution is correct
x/(3 x^2 + 2) ⇒ -(i sqrt(2/3))/(2 + 3 (-i sqrt(2/3))^2) = ∞^~
1/(24 x^2 + 16) ⇒ 1/(16 + 24 (-i sqrt(2/3))^2) = ∞^~:
So this solution is incorrect
x/(3 x^2 + 2) ⇒ (i sqrt(2/3))/(2 + 3 (i sqrt(2/3))^2) = ∞^~
1/(24 x^2 + 16) ⇒ 1/(16 + 24 (i sqrt(2/3))^2) = ∞^~:
So this solution is incorrect
The solution is:
Answer: |x = 1/8
sqrt(x) / [ sqrt(3)*x + sqrt(2) ] = 1 / [ 2*sqrt(6)*x + 4]
sqrt(x) / [ sqrt(3)*x + sqrt(2) ] = 1 / [(2(*sqrt(6)*x + 2) ] multiply both sides by 2
2sqrt (x) / [sqrt(3)*x + sqrt(2)] = 1 / [ sqrt(6)*x + 2] cross multiply
(2sqrt (x)) [ sqrt(6)*x + 2] = sqrt(3)*x + sqrt(2)
Factor sqrt (2) out of sqrt sqrt(6)*x + 2
[2sqrt (x) ] ( [sqrt (2)] * [sqrt(3) *x + sqrt(2)] ) = [ sqrt (3)*x + sqrt(2) ]
2sqrt(2)* sqrt(x) [ sqrt (3)*x + sqrt(2)] = [sqrt(3)*x + sqrt(2)]
2sqrt(2)*sqrt(x) [ sqrt (3)*x + sqrt(2)] - [sqrt(3)*x + sqrt(2)] = 0
[ sqrt (3)*x + sqrt(2)] [ 2sqrt(2)* sqrt(x) - 1 ] = 0
Set both factors to 0 and either
sqrt (3) * x + sqrt (2) = 0 → x = -sqrt (2)/ sqrt(3)
But this gives a non-real result to the original problem
Or
2sqrt(2) * sqrt(x) - 1 = 0
sqrt(8) * sqrt (x) = 1
sqrt (8x) = 1 square both sides
8x = 1 divide both sides by 8
x = 1/8
Hey CPhill, I was trying to follow the Guest's work and it looks like the first step was square every term. I was just wondering is that really allowed??
To be honest, hectictar, I wondered about that, too.....maybe the Guest knows something that we don't......!!!!
After looking at this problem again....I see that it's really very easy to solve
sqrt(x) / [ sqrt(3)*x + sqrt(2) ] = 1 / [ 2*sqrt(6)*x + 4]
sqrt(x) / [ sqrt(3)*x + sqrt(2) ] = 1 / [ (2)[sqrt(6)*x + 2 ] ] multiply both sides by 2
2sqrt(x) / [ sqrt(3)*x + sqrt(2) ] = 1 / [ sqrt(6)*x + 2]
Factor sqrt (2) out of sqrt(6)*x + 2 = sqrt(2) [ sqrt(3)*x + sqrt(2)]
2sqrt(x) / [ sqrt(3)*x + sqrt(2) ] = 1 / (sqrt(2) [ sqrt(3)*x + sqrt(2)] )
Multiply both sides by sqrt(2)
sqrt(2)*2sqrt(x) / [ sqrt(3)*x + sqrt(2) ] = 1 / [ sqrt(3)*x + sqrt(2)]
Since the denominators are the same, we can solve for the numerators
sqrt (2)* 2sqrt(x) = 1
2sqrt(2)sqrt(x) = 1
sqrt(8)sqrt(x) = 1
sqrt (8x) = 1 square both sides
8x = 1 → x = 1/8