# Relational understanding for a specific topic

I want to aproach the undertanding of the trigonometric function based on the concept of relacional undertanding, but I have problems to came up with and problemic situation for it. I mean I don´t want the first aproach to the students to be the typical unit circumference thing, I want they to comprenhend the how and why the trigonimetric function pop up the way they do.

For example: I read about some formulas for some geometric objects, there is the formulas and no more; by the other hand, in other place the authors intuitively explaned the notion of area in a rectangle, ans they use it for came up with all the formulas that in the first paper only apear of nowhere (parallelogram, traprice, irregular trapezoid, triangle and even circle).

• "by the other hand, in other place the authors intuitively explaned the notion of area in a rectangle" Can you share a link to one of these explanations that you like? Sep 30, 2020 at 2:14
• I don't have the link, i have the archive, and it's written in spanish Sep 30, 2020 at 2:33
• A geometry textbook usually introduces trigonometric functions in the chapter on right triangles, where sin, cos and tan are simply ratios between triangle's sides. Then a first-year physics course reinforces these concepts by solving problems with vectors and their projections. Sep 30, 2020 at 3:44
• Why do you want to avoid the unit circle approach? This is a very fundamental means of understanding the trig functions (like why it's even called tangent to start with) and there will be significant resources available about it, depending on where you look.
– Nij
Sep 30, 2020 at 3:48
• Because for the student, we have to related with significant context, not in the math it self but with another discipline or the daily life that conects with this and make that significance for the student, but it looks like here there are people that don't apreciatte that way, furthermore i didn't ask for if you belives about good or bad, there are studies that prove if is good or bad and way Oct 2, 2020 at 18:42