Double and Half Angle Formulas | Analytic Trig | Pre-Calculus

In this video we will explore how to use the double angle to evaluate trigonometric expressions from triangles as well as angles in degrees and radians. We will then use double angle formulas to help verify trigonometric identities and solve trigonometric equations.

I make short, to-the-point online math tutorials. I struggled with math growing up and have been able to use those experiences to help students improve in math through practical applications and tips.


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[Faresassadiii]

When the actual f am I gonna use any of this shi

[rknjlwg]

You’re the thank you for making this so smooth and easy 👌🏻❤️

[shavanianisha]

Shouldn't the answer at 33:46 be 1 and not 0?

[aaarcane]

Teacher just 1 question, from where country are you at?

Cuz you look like a cool math teacher that my school needs
😁

[matthewjamison]

Thank you for making this video. I like how you refer to tangent often. This is often overlooked in trig lessons.

[Bleshious]

how can I find the value of cos2(theta) if sin2(theta)=3/4 and theta is between 0 degrees and 90 degrees?

[djturnt]

I have a question. I hope you still read these. @35:35, There should be 2 different values for 2x. They are 3pi/2 and pi/2. If you and pi to either of those, you end up at the other. Why is a value of 3pi/2 not in the final solution? Is it considered an extraneous solution?

[apothe]

This was a really good lesson before my test Brian, thanks for a very thorough guide

[AdityaDonkada]

You are an absoloute top shotta I love your videos always coming in clutch

[georgebakradze]

At 30:07 for all solution if n equals 1 then we get negative so i guess pi/6 plus 2pin and 2pi/3+2pin is correctly

[RedaAQadri]

you are literally the only reason im passing

[georgebakradze]

I have 1 question Mr.Brian why we use at 34:22 set to equal 0 instead of division on sin squared ?

[ultimateasshole]

I just realize all those years and money I wasted in College back then, when Im getting all of these for free, instructive and convenient at the comfort of my home

[stevestef]

Great video,
btw at 33:33 you made a little error 3 divided by 3 = 1 not 0 lol, it happens

[kendrickskasusu]

How do you find the angle between 0°and 360° when the given equation is
Sin2x=2tan2x

[MrZackavelli]

In the first exercise, for cos (theta + theta), why is cos squared theta - sin squared theta equal to 2 theta? I thought it was equal to cos 2 theta

[noamlouzoun]

Why on student example 3 no.4 is it 2cos^2 i thought cos of 2x is just cos^2-sin^2

[huseyinhalitince]

Hi teacher İ guess you forgat the denominator expression at the 14:47 th minut of video

[kurt]

Hi Bryan. May I ask to you that you have FB account? Because I need your help.

[Danelatapia]

has anyone ever told you that you look like john fetterman