math

posted by .

what is the EXACT VALUE of cos (pi/3)?

  • math -

    from the 30-60-90 triangle

    cos 60º = cos pi/3 = 1/2

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. trig

    2sin(x)cos(x)+cos(x)=0 I'm looking for exact value solutions in [0, 3π] So I need to find general solutions to solve the equation. But do I eliminate cos(x), like this... 2sin(x)cos(x)+cos(x)=0 2sin(x)cos(x)= -cos(x) 2sin(x) = …
  2. MATH

    1.)Find the exact solution algebriacally, if possible: (PLEASE SHOW ALL STEPS) sin 2x - sin x = 0 2.) GIVEN: sin u = 3/5, 0 < u < ï/2 Find the exact values of: sin 2u, cos 2u and tan 2u using the double-angle formulas. 3.)Use …
  3. Math

    If sin(x) = /45 and cos(y) = 5/13 with both x and y terminating in quadrant 1 find the exact value of cos(x-y) cos(4/5 - 5/13) Is this what I would do?
  4. math

    If sin(x) = /45 and cos(y) = 5/13 with both x and y terminating in quadrant 1 find the exact value of cos(x-y) cos(4/5 - 5/13) Is this what I would do?
  5. Math

    For value cos (8ð/3). b) write cos (8ð/3) in terms of an algebraic sign and cosine of the reference angle find the exact value of what you found in part b using a cheating chart. no decimals please
  6. Trignometry questions EASY HELP

    1. Which is a solution to the equation below?
  7. Math- Trig

    1. Determine the exact value of cos^-1 (pi/2). Give number and explanaton. 2. Determine the exact value of tan^-1(sq. root 3). with explanation. 3. Determine exact value of cos(cos^-1(19 pi)). with explanation. 4. Determine the exact …
  8. math

    Determine exact value of cos(cos^-1(19 pi)). is this the cos (a+b)= cos a cos b- sina sin b?
  9. math

    determine the exact value of (cot pi/3) + (csc pi/3) / (cos pi/4). how is this calculated?
  10. Math

    Find the exact value of cos 1 degree + cos 2 degrees + cos 3 degrees + ... + cos 357 + cos 358 degrees + cos 359 degrees.

More Similar Questions