Is it possible to solve for L in this equation?
Thanks,
Aaron
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Q = 10L - 1/2000 (L)squared
I assume the -1/2000 (L)squared is -(1/2000)(L^2) so that the given
equation is quadratic only.
[If it were -1/(2000 L^2), then the given equation would be cubic.]
Q = 10L -(1/2000)(L^2)
Q = 10L -0.0005(L^2)
Put them all to the lefthand side,
0.0005(L^2) -10L +Q = 0
Use the Quadratic Formula,
L = {-(-10) +,-sqrt[(-10)^2 -4(0.0005)(Q)]} / (2* 0.0005)
L = {10 +,-sqrt[100 -(0.002)Q]} / 0.001
L = 10,000 +,-1000sqrt[100 -0.002Q]
That means,
L = 10,000 +1000sqrt[100 -0.002Q] ----***
or,
L = 10,000 -1000sqrt[100 -0.002Q] ----***
Q = 10L - 0.0005L^2 ?
If that's what you mean, ever hear of the quadratic formula?
Perhaps second post,sorry...had more to add.
Ever hear of quadratic formula? (The old b and +/- sqrt(4ac) thingy...)
Yes in terms of Q but not numerically unless you select a value for Q.
Otherwise, you have only one equation w/ two unknowns...
And, of course, there are limits on what Q can be if you wish to
restrict the solution to the real line rather than the complex plane...
More about what you want/need would be helpful...
> Q = 10L - 1/2000 (L)squared
>
> Is it possible to solve for L in this equation?
Sure is. You now know how many Ls make a Q, how do you think
you'd find out how many Qs you'd need for an L?
--Jeff
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will grow in strength in our land.
--Franklin Delano Roosevelt
Yes.
Assuming that the equation you meant to write was
Q = 10 L - (1/2000) L^2 ,
this is a standard quadratic formula and can be solved with any of the
techniques taught in Algebra 1 for solving quadratics.
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Kevin Karplus kar...@soe.ucsc.edu http://www.soe.ucsc.edu/~karplus
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L = 2000(5 +/- sqrt(25 + Q/2000))
--
I don't know who you are Sir, or where you come from,
but you've done me a power of good.
Q = 10L -(1/2000)L^2
Q = 10L -0.0005L^2
0.0005L^2 -10L +Q = 0
Use the Quadratic Formula,
L = {-(-10) +,-sqrt[(-10)^2 -4(0.0005)(Q)]} / (2*0.0005)
L = {10 +,-sqrt[100 -0.002Q]} / 0.001
L = {10 +,-sqrt[100(1 -0.00002Q)]} / (1/1000)
L = {10 +,-10sqrt[1 -0.00002Q]} * (1000)
L = 10,000 [1 +,-sqrt(1 -0.00002Q)]
That is it.