How to Use Product to Sum and Sum to Product Formulas in Trig (Precalculus - Trigonometry 29)

[@abnerflores-lezama7762]

Professor, I don't even take a math course anymore. You teach math so well that I just watch your videos for fun!

[@benji321]

you are a different breed my friend

[@EdTrainerTv]

I am writing to congratulate you on your educational content on KZbin. Your videos are clear, concise, and engaging, and they have helped me to learn a great deal about a variety of topics. Thank you for your dedication to education.

[@lelele7677]

ANOTHER BANGER BY PROFESSOR LEONARD

[@rwharrington87]

Haha

[@dragonlovesdiamond9512]

THANK IVE BEEN SPENDING 1-2 HOURS TRYING TO FIGURE THIS SIMPLE THING OMG THANK YOU IT JUST MADE IT CLICK🎉

[@kodya4]

Prof L you helped me so much in calc 1 this quarter! Brushing up on some trig for calc 2! Looking forward to the challenge, knowing it will be much more manageable with you by my side. Thanks for everything you do man!

[@dudestaytuned4542]

Thank you so much, Professor. You basically saved my scholarship. Btw, I miss the background sounds of the classroom in your videos haha, it made me feel like I was actually attending one of ur classes. Have a nice day

[@georgesadler7830]

Professor leonard ,thank you for another excellent video /lecture on How to use Product to Sum and Sum to Product Formulas in Trigonometry. Over time , just using these formulas are good enough to arrive at solutions to problems, by proving them my knowledge and understanding increase from start to finish.

[@neetugupta3373]

Hello sir I'm from India🇮🇳 Your teaching method is ingenious you're a fabulous teacher & thank you so much making this video for us🙏🙏

[@johnbandah2639]

You really know how to make things simple and clear 👏👏👏

[@lastdemon8648]

Came up at the right time Needed that Thanks professor

[@somasahu1234]

In the last example 3theta can be 6pi also !

[@aceystar1478]

yes but how do you derive the sum to product formulas?

[@uzairhussain4856]

you can prove these .take the R.H.S , apply appropriate product-to-sum formula on it, you will get L.H.S.

[@K1llerB333]

Can you do discrete structures?

[@wolfdd.5718]

In the example of before last (30:40) the angle should be - 2 not (-theta/2) right or i maybe wrong

[@1Vice876]

The 🐐

[@The_Angry_BeEconomist]

its a pity these formulas were not derived/proven- do we just have to memorise them?

[@Quinzer0]

Mannn this hurts wayyyyyy too much

[@ds5375]

I know what you mean. In this series I've gone from, "hm cool" to "ah awesome" to "why are we still on trig and when does end"

[@vasusrinivas4536]

the add given before the video looks like ai generated

[@tahagamal6282]

Well i used to hate math

[@somasahu1234]

First

[@alexanderyangov767]

It pains me to see your biceps became so small compare to the videos you made 10 years ago, although I am just a subscriber instead of student.

[@denisedattilo7880]

Wow, wish I could have a closer look at what you are doing, it's very a poor quality of the distance to us viewers!👎 Nice job explaining tho 😏