It is as easy as 1, 2, 3.......................AS IF..................the fact that the square root of 2 added to the square root of 3 is close to pi..............seems imp to me..........................30/60..........like 360........both a square and a circle have 360 degrees..........................the square root of 13 starts out..........3.60......................like full circle or full square..........a rectangle has 360 degrees as well....................



A fact you should commit to memory is:

The sides are in the ratio

 

1

:

2

:

√

3

Notice that the smallest side (1) is opposite the smallest angle (30°), and the longest side (2) is opposite the largest angle (90°). So while writing the ratio as 1: √3 :2  would be more correct, many find the sequence 1: 2: √3  easier to remember, especially when it is spoken. See also Side /angle relationships of a triangle. In the figure above, as you drag the vertices of the triangle to resize it, the angles remain fixed and the sides remain in this ratio.

Corollary

If any triangle has its sides in the ratio 1 - 2 - √3, then it is a 30-60-90 triangle.