Getting a shorter, more simple answer as output

How can I get a shorter answer, ideally an exact answer but decimal is also fine. This is my code:

syms x y
y=(log(x)/log(4))+(log(x^2)/log(4)); dy=diff(y)

Returns the answer as:

13510798882111488/(6243314768165359*x)

I'd like a simpler answer please such as:

3/(x*log(4))            % Exact answer

or;

2.1640/x                % Decimal approximation

Thanks.

Answer 1

[Walter Roberson]

syms x y
log4 = log(sym(4));
y=(log(x)/log4)+(log(x^2)/log4); dy=diff(y)

dy = 

[rezheen]

Hi Walter. When I run your code in Matlab (I have R2021a version), I get:

dy=2.1640/x

Which is great, but doesn't get what you get as output but that's probably because I have the older MATLAB version. Thanks for the answer.

[Walter Roberson]

You probably have

sympref('FloatingPointOutput', true)

ans = logical
   0

in effect. You want it to be false .

Answer 2

[rezheen]

I figured it out with this code:

sympref('FloatingPointOutput',true);
syms x y
y=(log(x)/log(4))+(log(x^2)/log(4)); dy=diff(y)

Output:

dy =
 
2.1640/x

Thanks in advance.