The following warnings occurred:
Warning [2] count(): Parameter must be an array or an object that implements Countable - Line: 795 - File: showthread.php PHP 7.4.33 (FreeBSD)
File Line Function
/showthread.php 795 errorHandler->error





Post Reply 
Question about Solve
08-25-2015, 07:16 AM (This post was last modified: 08-25-2015 07:22 AM by salvomic.)
Post: #1
Question about Solve
hi,
an Italian student asked to me what's the best way to solve these equations in Solve:

E1: A*(2*π*10)*COS(P)+11*A*SIN(P) = 0
E2: 11*A*COS(P)-A*(2*π*10)*SIN(P) = 23
where A is amplitude, P phase, the rest 2*PI*frequency (here 10 Hz)

I suggest only to set the Prime in DEG mode (he is to get something like 0.36 and 80°, he said).
I get different values with different invite suggestion for A and P (but they are values MOD 360, I think), however also about 0 and about 99.93 (giving A=0.001); giving for A 2 and for P 0 I get about 0 and about 80 also...
For examples the student got -20350160.0698 whit his tries:
-20350160.0698 MOD 360 is about 280 (about 279.93), that's 360-80...
Whit my values (about -0.36 and 99.93) the equations are consistent but a negative amplitude hasn't a physic sense.

But the guy is searching a general good solution if he doesn't know what invite values to give...
Suggestions?

Salvo

∫aL√0mic (IT9CLU) :: HP Prime 50g 41CX 71b 42s 39s 35s 12C 15C - DM42, DM41X - WP34s Prime Soft. Lib
Visit this user's website Find all posts by this user
Quote this message in a reply
Post Reply 


Messages In This Thread
Question about Solve - salvomic - 08-25-2015 07:16 AM
RE: Question about Solve - ww63 - 08-25-2015, 10:27 AM
RE: Question about Solve - salvomic - 08-25-2015, 10:29 AM
RE: Question about Solve - roadrunner - 08-25-2015, 12:44 PM
RE: Question about Solve - salvomic - 08-25-2015, 12:47 PM
RE: Question about Solve - DrD - 08-25-2015, 02:00 PM
RE: Question about Solve - salvomic - 08-25-2015, 03:43 PM
RE: Question about Solve - DrD - 08-25-2015, 07:50 PM
RE: Question about Solve - salvomic - 08-25-2015, 07:52 PM



User(s) browsing this thread: 1 Guest(s)