The Three Trigonometry Formulas
Trigonometry is all about relationships in right-angled triangles, and there are three key formulas you need to remember. Think of them as your mathematical toolkit for solving triangle mysteries!
The three trigonometric ratios are: Sin x = opposite/hypotenuse, Cos x = adjacent/hypotenuse, and Tan x = opposite/adjacent. The hypotenuse is always the longest side, the opposite is the side across from your angle, and the adjacent is the remaining side next to your angle.
Here's your game plan: first, work out which two sides are involved in your question. Then pick the formula that uses those two sides - it's that simple!
When you need to find an angle, use the inverse function by pressing 'shift' or '2nd' followed by sin, cos, or tan on your calculator. Just make sure your calculator is in DEG mode, and you'll see sinโปยน, cosโปยน, or tanโปยน appear on screen.
Top Tip: Remember SOH-CAH-TOA to recall which ratio uses which sides: Sin = Opposite/Hypotenuse, Cos = Adjacent/Hypotenuse, Tan = Opposite/Adjacent.