How to make γ the subject of the formula? (logarithms involved)

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SUMMARY

The discussion focuses on isolating the variable γ in the equation γ/γW = 0.27 [log Rf] + 0.36 [log((qnet+γ)/pa)] + 1.236, where γ represents the unit weight of soil. The known variables include γW (9.81), Rf (0.5), qnet (5.53), and pa (0.1). The solution involves manipulating logarithmic expressions and ultimately reveals that no closed form exists for this equation, necessitating the use of iterative approximation methods to solve for γ.

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How to make γ the subject of the formula? (logarithms involved)

Homework Statement



My problem here is that i want to make γ the subject of the formula so that i can calculate it since all other variables are know. As you can see from the equation below there are two γ inside the equation one on the left hand side and one on the right hand side of the equation which is inside the logarithm [log((qnet+γ)/pa)].

The variables involved are shown below, however you do not really need to know what each one means since the problem here is about mathematics and how to make γ subject of the formula if that's possible but i did include all variables to make it easier to understand the equation

γ = unit weight of soil = unknown
γW = unit weight of water = 9.81
Rf = friction ratio 0.5
qnet = net cone resistance = 5.53
pa = atmospheric pressure = 0.1

Homework Equations



Equation:γ/γW = 0.27 [log Rf] + 0.36 [log((qnet+γ)/pa)] +1.236

The Attempt at a Solution



γ/γW = 0.27 [log Rf] + 0.36 [log((qnet+γ)/pa)] +1.236

Substituting Rf = friction ratio 0.5

γ/γW = 0.27 [log 0.5] + 0.36 [log((qnet+γ)/pa)] +1.236

γ/γW = -0.08 + 0.36 [log((qnet+γ)/pa)] +1.236

γ/γW = -0.08 +1.236 + 0.36 [log((qnet+γ)/pa)]

γ/γW = 1.15 + 0.36 [log((qnet+γ)/pa)]

γ/γW - 1.15 = + 0.36 [log((qnet+γ)/pa)]

(γ/γW - 1.15)/0.36 = log((qnet+γ)/pa)

10(γ/γW - 1.15)/0.36 = (qnet+γ)/pa

I am not sure what to do next, i don't know how to get both γ together. Some help would be really appreciated.

Thank you.
 
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There is no closed form for mixes of functions like this. You will have to use approximation methods, iterative usually.
 


Ok thanks a lot for you reply
 

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