Basic Trigonometry Review

[cristy02]

thank you sooooooooo much this was so helpful to me remembering this for my college placement exam!!!!!

[Sduibek]

This would be better without the massive sibilance :(

[mrjohaneson]

@Sduibek Thanks for the comment. I think you worded it wrong, though. I'm pretty sure what you meant to type was, "Hey, thanks for helping me with my trigonometry :)" And then I would say...  you're welcome.

[QuadCore120]

Thanks! Reviewing them refreshes my mind!

[mrjohaneson]

@kuhataparunks I'm flattered to hear that I did better than Khan Academy. Thanks. Only please remember that you must use DEGREES MODE!!!! if you are working with angles in degrees. It's very rare in high school math that you'd be working with radians...until grade 12 math.

[kuhataparunks]

@mrjohaneson wow i wasn't thinking when i said radian lmao.... i really meant degrees :( i fewel stupid haha! :P but many thanks for deliberating your flattery ^_^

[BigA7XDog]

this helps out alot thanx bro



[pinoyoutoob]

how do you solve this? only the angle and opposite are given

[mrjohaneson]

@pinoyoutoob Remember that these are all RIGHT triangles, so you have one angle of 90° plus the angle given in the question. Subtract those from 180° to get the third angle. If you were given the opposite side, choose which other side to find first. If you choose the hypotenuse, then you'll use SIN. If you choose to find the adjacent, then use TAN. If you need both, do them one at a time using SIN & then TAN or find one and then use pythagoras' theorem for the third side.

[neobird13]

Thank you so much.

I have a bad math teacher and a short attention span.

You just saved my ass.

[kyerussell]

You are absolutely amazing. I'm usually a Khan Academy guy but his trig. explanations are horrible compared to this. THANK YOU SO MUCH.

[lltjekmeoutll]

how do you use a side and angle to get a side or another angle?

[mrjohaneson]

If you already know two sides, you can use Pythagoras' Theorem to find the third side (a squared plus b squared = c squared). If you know two angles and need to find the third angle, it's even easier since the three angles in a triangle always add up to 180°. Just do 180° minus the angle they gave you and minus the 90° angle in every right triangle. Whatever's left is the missing angle. Hope this helps.

[Hifcrea]

dude i fuckin love you. perfect video. you explained EVERYTHING i needed to finish this paper. explained nice and easy. anyone could understand

[Imakeplanesboom]

Aww, Ch. 1 review...

[tomyo669]

Helps a lot to see how they are used

[jmolina627]

Thanks for this basic review! I like the SOH CAH TOA. :)

[omydidick]

ughh calculator... of course.  my teacher doesnt let us use calculators

[mrjohaneson]

Without a calculator, the steps are exactly the same...except you need to use the tables to look up the decimal equivalent of Sine 25° (or whatever you are working with). Then, just multiply or divide as you would have with a calculator. The important thing to remember is that the steps remain exactly the same whether you're using a calculator or the trig tables.

[Capricho108]

OMG! thank you!!! i have hw about this due 2morrow and when i saw this I GOT IT INSTANTLY!! i rather have youtube as a math teacher than my own =p

[HaloFreakSpartan]

Thank you ur examples helped me a lot!

[Sham2951]

Thanks simple, neat & understanding... :)

[XxProductionxX]

thx this helped A L O T! =D

[XxProductionxX]

Thx this helped alot =D

[ExternalPk]

tysm

[rafaelxtianmorris]

thank u i hope i can pass my exam weehhhh ur good thank u again

[TheOwenmatthess]

Yo man, thanks, completely refressed everything from last year :]

[sweetemma111]

Perfectly clear, step-by-step explanation. Great job!

I find it very helpful.

[Sabu743]

nice vid... really helped me to review

[goop2526]

I am a 7th grader in advanced math and I missed this in class this really helps!!!

[tennist0]

my teacher gave the class this even though we learned it 3 years ago and the class unanimously forgot it, this helps alot

[penguinlogo]

im an eigth grader at the topof my class..and dis video helped me alot 5/5 and sub! another reason y youtube is the best

[sauty1]

I can show my kids...Cleared this up...You have any more?

[Claaavio]

thanks man, you cleared it up

[PessyRacoon]

This video saved my grade this session. Thank you.

[fricaledonia]

very good thank you

[Happyvicky123]

thanks so much.

i really didnt understand this now i do.

i really will remember this for my exams.

thanks :)

xx

[LovelyYTRocks]

Woohoo!

I'm learning!

[videosx18]

So clear and easy to understand.

Really good, thanks.

[hobokengar]

excellent presentation...just excellent !

[fnnypp1]

whoa. i learned part of this in pre-algebra

[cloudburst666]

Let's say you type in sin(65) in a calculator and it comes up with 0.91 (approximately). What exactly happened to the 65 to get 0.91? In other words, what calculation does sine, cosine, and tangent do to the angle when you type it in on a calculator?