| Title: | Mathematics at DEC |
| Moderator: | RUSURE::EDP |
| Created: | Mon Feb 03 1986 |
| Last Modified: | Fri Jun 06 1997 |
| Last Successful Update: | Fri Jun 06 1997 |
| Number of topics: | 2083 |
| Total number of notes: | 14613 |
Newsgroups: net.math Path: decwrl!decvax!harpo!eagle!mhuxl!houxm!ihnp4!we13!mgweed!rjr Subject: need help Posted: Tue Jan 31 09:21:53 1984 Perhaps some math whiz can help me out with a problem. I have a computer program that gives me an answer that is the sin of x. How can I get the value of x without an arc-sin function? My computer just has sin, cos, tan and arc-tan. (I also have the formula ACS(x)=-ATN(x/sqr(-x*x+1))+pi/2 which gives me the arc-cosine function). Tnx Bob
| T.R | Title | User | Personal Name | Date | Lines |
|---|---|---|---|---|---|
| 27.1 | HARE::STAN | Sat Feb 04 1984 15:36 | 1 | ||
ASIN(x) = pi/2 - ACOS(x) . | |||||
| 27.2 | RANI::LEICHTERJ | Mon Feb 06 1984 04:48 | 4 | ||
Another way to do it, ignoring ATAN altogether, is to do a Newton-Raphson approximation using SIN() - easy since SIN'=COS and COS(x) = SIN(90-X). I described this in more detail in a response on Usenet. -- Jerry | |||||