Hey there,
I have the following problem: let´s say I want to calculate the zero points of the cubic function:
f(x) = -2 x^3 + x^2 + 0.5 x – 8

I already know the respective solution:
p = roots([-2 1 0.5 -8])
The answer p is a vector with all three possible solutions.

Now my problem:
I would like to vary the third coefficient – that is 0.5 – by several values 0.1, 0.2, … , 0.5

That would be like

x=0.1:0.1:0.5;
p = roots([-2 1 x -8])

The problem is that the respective solutions are wrong.

What is my mistake?
How should I do it instead?

Thx a lot in advance!

Best regards,
TimHey there,
I have the following problem: let´s say I want to calculate the zero points of the cubic function:
f(x) = -2 x^3 + x^2 + 0.5 x – 8

I already know the respective solution:
p = roots([-2 1 0.5 -8])
The answer p is a vector with all three possible solutions.

Now my problem:
I would like to vary the third coefficient – that is 0.5 – by several values 0.1, 0.2, … , 0.5

That would be like

x=0.1:0.1:0.5;
p = roots([-2 1 x -8])

The problem is that the respective solutions are wrong.

What is my mistake?
How should I do it instead?

Thx a lot in advance!

Best regards,
Tim Hey there,
I have the following problem: let´s say I want to calculate the zero points of the cubic function:
f(x) = -2 x^3 + x^2 + 0.5 x – 8

I already know the respective solution:
p = roots([-2 1 0.5 -8])
The answer p is a vector with all three possible solutions.

Now my problem:
I would like to vary the third coefficient – that is 0.5 – by several values 0.1, 0.2, … , 0.5

That would be like

x=0.1:0.1:0.5;
p = roots([-2 1 x -8])

The problem is that the respective solutions are wrong.

What is my mistake?
How should I do it instead?

Thx a lot in advance!

Best regards,
Tim roots polynom or cubic funtion MATLAB Answers — New Questions

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