# Error using cos.Not enough input arguments.

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Cristian Rosca on 4 Sep 2020
Commented: Fangjun Jiang on 4 Sep 2020
Hi all,
Can anyone help me with this problem - Error using cos Not enough input arguments.
A2=sinh((x^2)+cos^2*y)^3/sqrt(abs(x-cos(y))+ln*(abs((x-cos(y)))/(x^2)+(cos^2)*y+abs(sin)*x))
Error using cos
Not enough input arguments.
i am new to matlab and i need to rezolve these expresition.

#### 1 Comment

Stephen Cobeldick on 4 Sep 2020
The function cos requires one input argument. As the error message states, you have called cos with no input argument, which throws an error. I have marked those locations for you, showing where you have called it incorrectly:
A2=(sinh((x^2)+(cos^2)*y)^3/sqrt(abs(x-cos(y)))+ln*(abs((x-cos(y))))/(x^2)+(cos^2)*y+abs(sin(y))*x)
% ^^^^ ^^^^
Your use of matrix operations is also quite likely to be incorrect:

Fangjun Jiang on 4 Sep 2020
try this line by line
y=pi
(cos(y))^2
cos^2*y

Show 1 older comment
Fangjun Jiang on 4 Sep 2020
You need to provide the original math equation.
Cristian Rosca on 4 Sep 2020
when x=-1.75*10^-3
y=3*pi
Fangjun Jiang on 4 Sep 2020
create some interim variables and build up your result
x=-1.75*10^-3;
y=3*pi;
cos_y=cos(y);
temp1=x^2+cos_y^2;
temp2=x-cos_y;
A2=sinh(temp1^3/sqrt(abs(temp2)))+log(abs(temp2/temp1))+abs(sin(y))*x

Steven Lord on 4 Sep 2020
In mathematics we write but when we implement that in MATLAB we implement it as [not to be confused with .]
x = pi/4;
y = cos(x)
z = cos(x).^2 % compare to y^2
w = cos(x.^2)

Cristian Rosca on 4 Sep 2020
i don't understand because i am beginner in matlab,maybe help me with this code?
Steven Lord on 4 Sep 2020
Run those four lines. See that z is the square of y. That is how you compute the square of the cosine of an angle. cos^2(x) is not valid MATLAB syntax.
Cristian Rosca on 4 Sep 2020
anyway is incorrect:((

R2016a

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