trig identities

• tanθ=


  sinθ/cosθ
• sinθ/cosθ=

  tanθ
• cotθ=


  cosθ/sinθ
• cosθ/sinθ

  cotθ
• cscθ=

  1/sinθ
• 1/sinθ=


  cscθ
• secθ=


  1/cosθ
• 1/cosθ=

  secθ
• cotθ=

  1/tanθ
• 1/tanθ=


  cotθ
• sinθ=


  1/cscθ
• 1/cscθ=

  sinθ
• cosθ=

  1/cscθ
• 1/cscθ=


  sinθ
• tanθ=


  1/cotθ
• 1/cotθ=

  tanθ
• sin²θ+cos²θ=

  1
• tan²θ+1=


  sec²θ
• 1+cot²θ=


  csc²θ
• 1-sin²θ=


  cos²θ
• 1-cos²θ=

  sin²θ
• cos²θ-1=

  -sin²θ
• sin²θ-1=

  -cos²θ
• tan²θ+1=


  sec²θ
• sec²θ-1=

  tan²θ
• sec²θ-tan²θ=

  1
• 1+cot²θ=


  csc²θ
• csc²θ-cot²θ=

  1
• csc²θ-1=

  cot²θ
• sin is short for...

  sine
• cos is short for...


  cosine
• tan is short for...

  tangent
• csc is short for...

  cosecant
• sec is short for...


  secant
• cot is short for...

  cotangent
• cosecant is the reciprocal of...

  sine
• secant is the reciprocal of...

  cosine
• cotangent is the reciprocal of...

  tangent