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Really Need Help Doing this Nonlinear System Problem

JoshMyers
1-Newbie

Really Need Help Doing this Nonlinear System Problem

Hello Everyone!

Okay everytime I try to solve this non linear equations the x and y keeps saying undefine before I can get to the iterations.

Can someone please help me? Thanks!

You can attach the mathcad file or .rtf file. Thanks!

I am also attaching the problem in word!

1 REPLY 1
StuartBruff
23-Emerald II
(To:JoshMyers)

Josh Myers wrote:

Hello Everyone!

Okay everytime I try to solve this non linear equations the x and y keeps saying undefine before I can get to the iterations.

Can someone please help me? Thanks!

You can attach the mathcad file or .rtf file. Thanks!

I am also attaching the problem in word!

Solve the following nonlinear system until the values of x and y converge with a percent relative error of less than 1% for both variables. Solve equation #1 for x and solve equation #2 for y and begin the iterative process with an initial guess of

x = 0 and y = 0. Format all calculations to 10 decimal places.

X^3 + 4y^2 = 16 (Equation 1)

2 ln(0.25x) - y = 0 (Equation 2)

Hi Josh,

You'll find that it's better to attach a worksheet even if it's got mistakes. For a start, it saves readers having to type in expressions and second it can be difficult to find typos or other problems just from a description or screen shot.

The best way to solve this problem is probably using a solve block - see attached. Solve blocks require a guess value for each variable, so Mathcad is probably complaining about this is you don't have expressions such as x:=0 and y:=0 before the start of the solve block.

However, one slight problem with the initial guesses is that ln(x) is not defined for x=0, so you will have to pick a slightly different initial value.

Stuart

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