Further Trigonometry | Proving The Sine Rule, Cosine Rule & Area of a Triangle using Sine (Grade 9)

A video revising the techniques and strategies for proving the trigonometric rules, the sine rule, cosine rule and area of a triangle using sine.

This video is part of the Further Trigonometry module in GCSE maths, see my other videos below to continue with the series.

These are the calculators that I recommend:

🔹 Watch the video
🔹 Make notes
🔹 Practice the questions
🔹 Mark your work
🔹 Review what you have learnt on the exam questions

Please like ✅ please comment ✅ please subscribe ✅

Enjoy the video!

Follow me here:

Music: That Day
Musician: Jef

[dodgespecialist]

So interesting, could you prove the quadratic formula?

[shabadkaur]

Awesome flawless explanation SIR!!! Salute to such a great teacher

[GXT_ROGUE]

Yo, im almost ready for Maths exam on the 13th, just curious when u will start the revision lives and vids before exams

[GCSEALevelMaths]

Great video sir good job!! Really well explained!!

[dacatnextdoor]

Question: would we get asked about Proving the sine rule, the cosine rule & area of a triangle using sine in the papers?

[calcpost]

Sir for proving the area of a triangle do we just assume that the perpendicular height bisects the side CB?

[finnrattray]

I’m calling it, one of these is gonna be the last q on paper 2 of 2022 edexcel paper.

[bigwizard]

15:41 since we don't have any values of lengths, couldn't we also use TOA since we "have" opposite like we have the hypotenuse? I don't understand how we could know to use COS.

[vascobishop]

Clever. More words will merely spoil the whole issue.

[giyrglj]

hi sir could this sort of question come up in the exam ? eg, , prove this triangle using sine rule?

[shabadkaur]

plz explain the triangle at timestap 5:29 too

[Luka_c]

for the area of a triangle you mention that the base of one of the right angel triangles in that one irregular triangle has base "a". wouldn't it be "a-x" as it is not the full length?

[ibrahimuddin]

is this further maths or normal gcse maths?

[eipimath]

Thanks for sharing! I posted a short video on deriving the law of cosines, It should apply for all angles (acute, obtuse, reflex, negative). Hope to get your thoughts.

[INeedGooderGrades]

how about proving the quadratic formula and pythagoras

[shllie]

theres noi way theyre gonna ask u this