Syntax error in function block of simulink

I am trying to implement a function using simulink, but it throws syntax error. I am using mux with 4 inputs to feed to the function block.

( (u(1)*sin(u(2))) + (u(3)*cos(u(2)))) * sec(u(4))

This is the function which I am trying to implement.

Answer 1

[Ankit]

Please refer to the below link to find out the supported Trignometric Functions:

https://de.mathworks.com/help/simulink/slref/trigonometricfunction.html

((u(1)*sin(u(2))) + (u(3)*cos(u(2))))*acos(u(4))