PDA

View Full Version : Addition of sin and cos


Ry122
Mar30-07, 08:28 AM
does cos + sin = 0?

neutrino
Mar30-07, 08:33 AM
cos + sin can never be equal to anything other than cos + sin. sin and cos are just functions. Neither has a "value" as such.

Do you want to if sin(somevalue1) + cos(somevalue2) = 0?

sutupidmath
Mar30-07, 09:22 AM
does cos + sin = 0?

like neutrino said cos + sin have no meaning. But if we get let's say

sin(2n pi)+ cos[(pi/2)+n pi] =0, and there are more samples like this. if this is what you meant at first place?????

f(x)
Mar30-07, 01:16 PM
did you mean cosx+sinx=0 ?
\mbox{for the above to be true},\\ cosx=-sinx \\ \Rightarrow cotx=-1 (or sinx=0 but this does not hold for that.)

ChaoticLlama
Mar30-07, 01:29 PM
Please only post calculus questions in this forum.

f(x)
Mar30-07, 01:43 PM
Please only post calculus questions in this forum.
LOL,this may well be calculus.....
Max(sinx+cosx)= \sqrt{2}
Min(sinx+cosx)= -\sqrt{2}
Since they function is continuous, it must have x such that f(x)=0

Gib Z
Mar30-07, 08:58 PM
To OP: Short answer. No.

Gib Z
Mar30-07, 08:59 PM
Wait up, perhaps you got confused with this:

\cos^2 x + \sin^2 x = 1