Check for incorrect argument data type or missing argument in call to function 'diff'.

>> f

f =

Inline function:

f(x) = ((x+2)^(2/3))(3*x^2 -2)^3)

>> diff(f,x)

Check for incorrect argument data type or missing argument in call to function 'diff'.

Find the derivative of the function: . This is the intended equation.

Have I input it correctly or am i missing something?

[Jan]

Do you want a symbolical or numerical output? Why do you use inline? This is outdated for over 10 years.

Answer 1

[Kunal Kandhari]

The correct piece of code will be:

f = inline('((x+2)^(2/3)*((3*x^2)-2)^3)','x')
ans = f(1)

matlab will internally convert it to:

f =

Inline function:

f(x) = ((x+2)^(2/3))*(3*x^2 -2)^3)

You can refer:

https://in.mathworks.com/help/matlab/ref/inline.html

Althrough inline will be removed in a future release. Use anonymous functions instead.

Answer 2

[Mahesh Taparia]

Hi

It seems you are finding derivative of a function of x. If you don't have the value of x, then you can go by symbolic approach. For example, consider the code below:

syms x
y = ((x+2)^(2/3))*(3*x^2 -2)^3;
yDerivative = diff(y);

If you have the sample values of x, then use last 2 lines of code. For more information, you can have a look at the documentation of diff function here.

Hope it will help!