matlab - Find minimum of single-variable function

Question

I have a Matlab question:

What expression is calculated by the following command in Matlab? Code: fminbnd(@(x) (sin(x).^2-1),0,pi) Minimum of: (a) f(x)=1-sin x^2 or (b)1-sin^2x.

I am not really sure. I have pluged the x values into both of my options and the one that returns the matching y value is the correct function. BUt for both equations i get 1, so i don't know what is right a) or b)?

question from:https://stackoverflow.com/questions/65896899/find-minimum-of-single-variable-function

Answer 1

Function evaluations have higher precedence than raising to a power. So

sin(x).^2-1

is the same as

(sin(x)).^2-1

I.e., you do the sin(x) first, then square this result. Which is not the same as

sin(x.^2)-1