Trigonometry - AKE

Trigonometry - AKE

1. Trigonometry (from Greek trigonon, "triangle" and metron, "measure") is a branch of mathematics that studies relationships involving lengths and angles of triangles.

   • Always use 'SHIFT' on a calculator when finding the acute angle of the triangle.
   • Do not use 'SHIFT' on a calculator when finding the length of a side in the triangle.

2. Sine - trigonometrical function of an angle, the sine of an acute angle is defined in the context of a right angle: for a specific angle.

   • It is the ratio of the length of the side that is 'opposite' that angle to the length of the longest side of the triangle also known as the 'hypotenuse'!
   • Sin x = Opp / Hyp

3. Cosine - the trigonometric function of an angle, the cosine of an acute angle is defined in the context of a right angle: for a specific angle.

   • Cos x = Adj / Hyp
   • It is the ratio of the side 'adjacent' to an acute angle (in a right-angled triangle) to the 'hypotenuse'.

4. Tangent - trigonometrical function of an angle, the tangent of and acute angle is defined in the context of a right angle: for a specific angle.

   • It is the ratio of the side of the 'opposite to an acute angle to the 'adjacent'.
   • Tan x = Opp / Adj