# Trig function notation

Discussion in 'Mathematics' started by shirtandtie, Feb 20, 2012.

1. ### shirtandtie

I'm thinking of changing all my teaching notes to show trig functions as sin(x), tan(theta) in all circumstances.
In otherwords to always show the subject of the trig function in brackets, as this seems most consistent to me (and Mr Casio), and less confusing to students.
But could I be making a mistake?

2. ### ian60New commenter

I'm a bit confused, how have you been doing this before in your notes?

3. ### strawbsOccasional commenter

I guess OP means just as sin 60 as opposed to sin (60)

4. ### atics

I can see why this would be a good idea - it does no harm but could encourage students to understand that it is a function, i.e. something is done to the angle.

5. ### PaulDGOccasional commenter

The fx-83GT+ on the table next to me is quite happy to give me the correct answer when I type "sin" "6" "0" "=".

(What I know confuses the students isn't the bracket, but the fact that the answer is shown as root 3 / 2 ... Though it's not too hard to remind them to press the "S-D" button and some of the advanced ones can even remember to press "shift" before pressing "=". Top sets can even be OK with root 3/2 !!)

7. ### shirtandtie

So does mine, but it adds an opening bracket, which must be closed if a second expression is to be evaluated in the same step.

8. ### PiranhaStar commenter

But won't your students go on to take public examinations?
Thanks, Anna Luise, that is the thread I was refering to.

9. ### luke_howells

True, until you see students think that when they see sin(f(x))=c this means that sin has been factored out of an expression and their next step is to try and divide by sin in order to determine f(x), ie f(x)=c/sin, rather than f(x)=arcsin c!