Determining the equation of a trig function | Graphs of trig functions | Trigonometry | Khan Academy

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Trigonometry on Khan Academy: Big, fancy word, right? Don't be fooled. Looking at the prefix, tri-, you could probably assume that trigonometry ("trig" as it's sometimes called) has something to do with triangles. You would be right! Trig is the study of the properties of triangles. Why is it important? It's used in measuring precise distances, particularly in industries like satellite systems and sciences like astronomy. It's not only space, however. Trig is present in architecture and music, too. Now you may wonder...how is knowing the measurement and properties of triangles relevant to music?? THAT is a great question. Maybe you'll learn the answer from us in these tutorials!

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[AtinsMusic]

I would love learning this in school if I wasn't only studying for a good grade. Wish me luck on tomorrows test :)

[ilyoserkulov]

Salman Khan, there is a lack of videos about trigonometric transformations in your academy's trigonometry module

[blockPawn]

do you have a video on
how to do this with C in the equasion
y=asin[b(x-c)]+d
the c is the hardest part for me

[magicmike]

Wow trig functions are awesome! Im taking trig this coming spring semester

[apollosleaf]

To find the phase shift find all the values in the vid. Take a point from the graph in this case (2, 1) sub it in and solve for d

[Mj]

the equation could also be f(x) = 3 cos pi/4*(x-2) - 2

[HaiNguyen-frxf]

I think this equation lacks of the horizontal shift

[jbill]

Can "f(k)" be translated to the "function of a coefficient"? Is that correct interpretation? Homework problem is determining the period r of f(k) = a ^k mod M EDIT: where a is a random integer.

[nobodyaskedforthis.]

My book says a=max-min/2 meaning the amplitude should be 3, not 2

[adamdee]

how do you figure out the phase shifts though?

[oneuniqueusername]

omg where did 2 pi come from out of nowhere

[jasonenns]

I know an easier way all I did and I do not know trig that well is p/2pi=k