1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Addition of sin and cos

  1. Mar 30, 2007 #1
    does cos + sin = 0?
  2. jcsd
  3. Mar 30, 2007 #2
    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?
  4. Mar 30, 2007 #3
    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?????
  5. Mar 30, 2007 #4
    did you mean [tex]cosx+sinx=0 [/tex] ?
    [tex]\mbox{for the above to be true},\\ cosx=-sinx \\ \Rightarrow cotx=-1 [/tex] (or [tex]sinx=0[/tex] but this does not hold for that.)
  6. Mar 30, 2007 #5
    Please only post calculus questions in this forum.
  7. Mar 30, 2007 #6
    LOL,this may well be calculus.....
    [tex]Max(sinx+cosx)= \sqrt{2}[/tex]
    [tex]Min(sinx+cosx)= -\sqrt{2}[/tex]
    Since they function is continuous, it must have x such that f(x)=0
  8. Mar 30, 2007 #7

    Gib Z

    User Avatar
    Homework Helper

    To OP: Short answer. No.
  9. Mar 30, 2007 #8

    Gib Z

    User Avatar
    Homework Helper

    Wait up, perhaps you got confused with this:

    [tex]\cos^2 x + \sin^2 x = 1[/tex]
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Similar Discussions: Addition of sin and cos
  1. Cos and sin cont (Replies: 1)

  2. Sin and Cos (Replies: 7)

  3. Sin/cos/tan by hand? (Replies: 2)