Rearranging Formulas: Fairly simple but I'm very stuck

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The discussion focuses on rearranging the formula T = 2π√(l/g) x^2 to isolate g. The initial steps of dividing by 2π and squaring were debated, with advice given to first isolate the square root by dividing by x^2. It was clarified that squaring both sides should occur after isolating the square root, leading to the equation g = (4π^2Lx^4)/T^2. The final confirmation reassured the user that their derived formula for g was correct. The exchange highlights common pitfalls in algebraic manipulation and the importance of careful step-by-step isolation.
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Homework Statement


Change the subject of the equation to (g)

Homework Equations


T = 2π√l/g x^2

86903828c3a4e638e3cbb27ab441fa67661bd89839ff26393fd3fbf0ab9e647a19972838.jpg


The Attempt at a Solution



In my attempt I've divided both sides by 2π for
T/2π = √l/g x^2

Then I decided to square both sides for

(T/2π)^2 = l/g x^2

Now I'm really not sure if what I've done so far is off or I'm on the right track?
I'm usually ok when it comes to this but for some reason this has caught me out
Any help would be greatly appreciated, thanks.
 

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Alexander8 said:
Then I decided to square both sides for

(T/2π)^2 = l/g x^2
It's not time to square both sides yet (and you only squared the left side anyway).

Instead, divide both sides by x^2 so you get just the square root on the righthand side (RHS). Then it will be time to square both sides of the equation and continue doing the algebra to isolate g.
 
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I don't know how the ## x^2 ## got in there=usually this equation reads ## T=2 \pi \sqrt{\frac{l}{g}} ##, but assuming the ## x^2 ## belongs there, it becomes an ## x^4 ## when you square both sides. ## \\ ## To solve for ## g ## , one helpful hint is you can multiply both sides of the equation by ## g ## . The ## g's ## will cancel on the right side, and it will be in the numerator on the left side.
 
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berkeman said:
It's not time to square both sides yet (and you only squared the left side anyway).

Instead, divide both sides by x^2 so you get just the square root on the righthand side (RHS). Then it will be time to square both sides of the equation and continue doing the algebra to isolate g.

So my first step of dividing both sides by 2π to give

T/2π = √l/g x^2

is correct?
 
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Charles Link said:
I don't know how the ## x^2 ## got in there=usually this equation reads ## T=2 \pi \sqrt{\frac{l}{g}} ##, but assuming the ## x^2 ## belongs there, it becomes an ## x^4 ## when you square both sides. ## \\ ## To solve for ## g ## , one helpful hint is you can multiply both sides of the equation by ## g ## . The ## g's ## will cancel on the right side, and it will be in the numerator on the left side.

Yeah I found that equation without the x^2 asked on here previously, but for some reason the question we've been given includes the additional x^2
 
Sorry to message again, but I've got:

g = (4π2Lx4)/T2

Is that correct or am I way off?
 
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Charles Link said:
@Alexander8 It's correct.
Ahhh panic over. Thank you very much for the help!
 
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