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Question
Solve for x, if `5/x + 4sqrt(3) = (2sqrt(3))/x^2, x = 0`
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Solution
Given: `5/x + 4sqrt(3) = (2sqrt(3))/x^2, x = 0`
Step-wise calculation:
1. Multiply both sides by x2 valid since x ≠ 0:
`5x + 4sqrt(3)x^2 = 2sqrt(3)`
2. Rearrange to standard quadratic form:
`4sqrt(3)x^2 + 5x - 2sqrt(3) = 0`
3. For `a = 4sqrt(3), b = 5, c = -2sqrt(3)`
Compute the discriminant:
Δ = b2 – 4ac
= `25 - 4(4sqrt(3))(-2sqrt(3))`
= 25 + 96
= 121
4. `sqrt(Δ) = 11`.
Apply the quadratic formula:
`x = (-b ± sqrt(Δ))/(2a)`
= `(-5 ± 11)/(8sqrt(3))`
5. Compute the two roots:
`x_1 = (-5 + 11)/(8sqrt(3))`
= `6/(8sqrt(3))`
= `3/(4sqrt(3))`
= `sqrt(3)/4`
`x_2 = (-5 - 11)/(8sqrt(3))`
= `(-16)/(8sqrt(3))`
= `(-2)/sqrt(3)`
= `(-2sqrt(3))/3`
The solutions are `x = sqrt(3)/4` and `x = (-2sqrt(3))/3` both nonzero, so both valid.
