# Sinc functions

• Feb 17th 2008, 04:44 PM
crane_2001
Sinc functions
If sinc(x)=0.707.. what is x..
How do we calculate this
Thanks
• Feb 17th 2008, 05:18 PM
Plato
Quote:

Originally Posted by crane_2001
If sinc(x)=0.707.. what is x.. How do we calculate this?

What is the function $sinc(x)$?
• Feb 17th 2008, 06:16 PM
TwistedOne151
Are you using the normalized or unnormalized sine cardinal function?
-Kevin C.
• Feb 17th 2008, 06:18 PM
crane_2001
sinc function
normalised
• Feb 17th 2008, 07:48 PM
mr fantastic
Quote:

Originally Posted by crane_2001
If sinc(x)=0.707.. what is x..
How do we calculate this
Thanks

Quote:

Originally Posted by crane_2001
normalised

You're asking how to solve $\frac{\sin (\pi x)}{\pi x} = 0.707 ..$. You can't get an exact value in closed form. It's an example of a transcendental equation.

If you're only interested in calculatiing a numerical approximation to the exact value, then there are many options.