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Trigonometry Question Help

Hi there,
I was just wondering if anyone could help me with this question:

Without using a calculator, evaluate the expression, simplifying it as far as possible:
1-sin^2(pi/6)

Thank you :smile:
Not sure if this is some h/w question, so I will give you a hint, instead of a full solution:

There are certain angles for which we can calculate exact values of their sine, cosine, etc...
pi/6 is one of those angles. If you don't remember the exact value of sin(pi/6), try referring to your textbook/notes, it should be there.
After that the question is just arithmetic.

Hope this helped.

EDIT: You could also use a well-known trig identity to simplify the expression a bit, although it's not really necessary.
(edited 2 years ago)
Hi, thank you for your response.
It was just a workbook question that i came across after a while.
Thank you that makes sense, i was just confused on like do i have to use any trig identities but now i understand it.:smile:

Original post by The Malevolent
Not sure if this is some h/w question, so I will give you a hint, instead of a full solution:

There are certain angles for which we can calculate exact values of their sine, cosine, etc...
pi/6 is one of those angles. If you don't remember the exact value of sin(pi/6), try referring to your textbook/notes, it should be there.
After that the question is just arithmetic.

Hope this helped.

EDIT: You could also use a well-known trig identity to simplify the expression a bit, although it's not really necessary.

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