Trig

• For which values of x between 0 degrees and 360 degrees in sinx equal to 0?


  0, 180 and 360
• For which values between 0 degrees and 360 degrees in cosx equal to 0?


  90 and 270
• For which values between 0 and 360 degrees in tan x equal to 0?


  0, 180 and 360
• What is the formula for sin in a right-angled triangle?


  Opposite over Hypotoneuse
• What is the formula for cos in a right-angled triangle?


  Adjacent over Hypotenuse
• What is the formula for tan in a right-angled triangle?


  Opposite over adjacent
• What is sin30?


  1/2
• What is cos30?


  √3/2
• What is tan30?


  1/√3
• What is sin60?


  √3/2
• What is cos60?


  1/2
• What is tan60?


  √3
• What is sin45?


  1/√2
• What is cos45?


  1/√2
• What is tan45?


  1
• What is cos0?


  1
• What is sin90?


  1
• What is cos180?


  -1
• How do you change from radians to degrees?


  Divide by Pi and multiply by 180 degrees
• How do you change from degrees to radians?


  Divide by 180 and multiply by Pi
• What is 180 degrees in radians?


  π
• What is 360 degrees in radians?


  2π
• What is 90 degrees in radians?


  π/2
• What is the formula for tan?


  sinx/cosx
• How is the range of sinx and cosx restricted?


  It is between 1 and -1
• How do you find the amplitude of a trig function from its equation?


  It's the number in front of sin, cos or tan.
• How do you find the frequency of a trig function from its equation?


  It's the number infront of x
• What are the three steps to solve an equation containing cossquaredx or sinsquaredx?

  1. Rearrange to get zero on the RHS
  2. Factorise it
  3. Use each bracket to make a new equation
• If you know solutions between 0 and 360 degrees, how can you find other solutions?

  Add or take away multiples of 360 degrees.