[Fingers samgakbi] How to obtain the special samgakbi of each finger

How to never forget the triangular ratio of the special angle

In the past, trigonometric functions were included in the second semester of high school, so they used to tell exactly what Menmbung was. Nevertheless, the triangle angle of the special angle below is a junior high school, so it must be memorized. The triangular ratio of the special angle is hard to express, but it shows its own rules (rules are easy to memorize).

fingers

It’s easy to remember this way.

calculations

Triangular ratio of special angle using finger sin60 °, cos60 the ° seek ways

Sometimes I can not remember the triangular ratio of the special angle, using the fingers can easily obtain the triangular ratio of the special angle.

hand-degrees

  • (Step 1) Extend your left hand so that your palm is visible.
  • (Step 2) Write 0 °, 30 °, 45 °, 60 °, 90 ° on the thumb, forefinger, middle finger (stop), weak finger (ring finger), and little finger.
  • (Step 3) Count the number of fingers on the left and the number of fingers on the left of the baseline (pink line) pointing to 60 °.
  • (Step 4) There are three fingers on the left of the baseline and one finger on the right.

ipdewnnr457eh2

ipdex7vcdycd2m

 

Triangular ratio of special angle using finger sin90 °, cos90 the ° seek ways.

90-degree.png

  • (Step 3) Count the number of fingers to the left and the number of fingers to the left of the reference line (orange line) that points to 90°.
  • (Step 4) There are four fingers on the left of the baseline and zero fingers on the right.

ipdf6uhitkp698.jpg

ipdg45bgp5h3iu

 

 

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.