Pythagorean

This applies to rules with a P scale.

To find the value of Ö(1-x²):

• Move the cursor to the x value on the D scale.
• Read the value of Ö(1-x²) on the P scale.

This scale can be used either for right angled triangles or for converting sin to cos (and vice versa).

For right angled triangles, c² = b² - a²

then
c = b Ö(1- (a/b)² )

Example:
    b=5.0 and a = 3.0 How long is c
    Calculate a/b = 3.0/5.0 = 0.6
    Cursor to 0.6 of Pythagorean scale (marked Ö(1-s²) and highlighted in green.)
    10 on C to cursor,
    Answer (4.0) under 5.0 on D.

For cosine the formula is:

cos = Ö(1- sin²)