How to solve trigonometric equations using the Quadrant Rule (negative angles) 

The way you explain is so simple compared to other people it's ridiculous. Thank you for taking the time to show us all!

you saved me because I will have test on this next week. I didn't know much about this topic. my class teacher used graphs for this and I didn't get anything. thank you so much , you made this so easy.

You made the whole chapter really easy for me sir.... Hope we have teachers in our local schools... May you get the best out of your work

this is the only topic i dreaded (oh, and functions too.) to do because i could not seem to understand a word my teachers said, but you literally made it so easy and fun. I am so thankful to you. May God bless you.

I've been making the mistake of dividing the angle first then using to find my solutions for a very long time.... Thank you for correcting me before my final exam next month!!

Your work is much appreciated mate, people all the way here in Australia learn from your work

This playlist is freaking gold

Thank you so much.. I had been trying to understand this for months until i came across your video making this crystal clear..once again thanks.

Thank you so much, all your videos are so helpful!Amazing channel.:)I had a slight doubt in the last question in the end why do you change the angle values to +/- when multiplying by 3 to find 4 theta?

Great video. I would have struggled with this concept for a while had I not come upon your channel. I'm glad you changed the range in the examples; it made it all click.

That was really helpfull..tq😊

Mate thanks for all the help! This helped me clear a lot of doubts!!! Stay safe and bless your kind soul. Please do keep up this quality work!

Thank u so much,i will have an exam just 3 hours later and u just saved my life,thank u sir.

thank you kind sir wish you all the best

thanks a lot ,very helpful videos .

tysm. i cant tell you how i appreciate this. youre amazing

Thank You, This was really helpful. Just wanted to know why it would be wrong if you divided the first equation by 2 on both sides before doing anything else. When can you simplify equations by doing that then?

i wish you were my maths teacher sir,thanks for the video ,very informative

You are simply the best!

@ExamSolutions for question 1, why not just rearrange for theta instead of 2theta?

Thanks alot!

So if the theta is divided or multiplied by any number, we just turn it over 360 degrees and get two more values. Have I gotten it right?

Thanks for the videos! Do we have to always do a cast diagram for these types of trig questions? As for some e.g. tan of an angle, I know the period of the tan graph is 180 degrees/pi, so I just keep adding or subtracting 180 degrees from the calculator solution for alternative solutions until I'm out of range. Would this also be acceptable? (for A2 edexcel maths) Thanks

If a question is: sinθ = ±√(0.75) for 0°

is cos theta the same as cos x

thank you

Why do we change the range?

veryyyy goooddddd :D

But how do you find 236.25 degree by not changing ranges

Thank you very much for these helpful and informative videos. However, I'm very confused due to the ending. Isn't 4/3 of 45 degrees 60? Not 33.75? And vice versa for -315, -420 degrees, not -236.25?

I appreciate your videos a lot but here you show a pretty complicated technique to solve the equations whereas they are done in a different and easier method in the examples of the books.

ez