1. ## Idle curiousity

How do I evaluate a trig function like $sin(4)$ without a calculator? Assuming that, since there is no unit, it's 4 radians...

2. ## Re: Idle curiousity

Originally Posted by Nervous
How do I evaluate a trig function like $sin(4)$ without a calculator? Assuming that, since there is no unit, it's 4 radians...

I would look it up in a trig table.

3. ## Re: Idle curiousity

How would I construct a trig table?

4. ## Re: Idle curiousity

Originally Posted by Nervous
How would I construct a trig table?
http://www.math.rutgers.edu/~cherlin...2000/hunt.html

5. ## Re: Idle curiousity

Although it is NOT the way trig tables are constructed, the simplest thing to do is to use "MacLaurin" series for sin(x):
$sin(x)= x- \frac{x^3}{3!}+ \frac{x^5}{5!}- \frac{x^7}{7!}+ \cdot\cdot\cdot+ \frac{x^{2n+1}}{(2n+1)!}+ \cdot\cdot\cdot$