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Thought-Process to Discover Knowledge

Welcome to nubtrek.

Books and other education websites provide "matter-of-fact" knowledge. Instead, nubtrek provides a thought-process to discover knowledge.

In each of the topic, the outline of the thought-process, for that topic, is provided for learners and educators.

Read in the blogs more about the unique learning experience at nubtrek.continue
9th-10th Foundation


Welcome to the only place where the essence of trigonometry is explained.

 •  a right-triangle is specified by 2 independent parameters.

 •  That means, if an angle and the length of a side is given, then one should be able to calculate the length of the other two sides.

 •  What property one can use to calculate the above? For a given angle, the ratio of sides is a constant.

Thus, the ratio of sides comes into existence as `sin`, `cos`, `tan` etc. The thought-process is revolutionary and aweinspiring.

Beyond the definitions of trigonometric ratios, the following are covered.

 •  trigonometric ratios for standard angles

 •  trigonometric identities based on Pythagoras Theorem
(click for the list of lessons in this topic)

Basics of Trigonometry

In this lesson, first the basics required to understand trigonometry are revised. Then, the revolutionary and aweinspiring explanation of trigonometric ratios is provided.

 •  A triangle has `6` or `7` parameters (`3` sides, `3` angles, sometimes height as the `7`th parameter)

 •  It has `3` independent parameters, meaning the other parameters can be calculated from the given `3`.

 •  A right triangle has `2` independent parameters, as one angle is already given as `90^@`.

 •  Given an angle and a side (which are the `2` independent parameters), how to compute the other two sides?

 •  The answer is that, given an angle, the ratio of two sides is a known constant. So, the known constant and the given side are used to compute the other sides.

This leads to defining the trigonometric ratios (ratio of sides as known constant) `sin`, `cos`, `tan`.

(click for the list of pages in the lesson)