Edexcel A Level Maths: 6.4 Trigonometric Identities (Peter is my students name)

[@zidanemehmood7424]

Very juicy tekky equations you have submantled their Zeeshan

[@moginger8018]

hey hey

[@hasib2312]

If this guy was my maths teacher I would defo get an A*

[@eragon1378]

You've got his vids here - no excuse cmon.

[@youremyaddiction3801]

Who's that lucky peter man😂😂😂

[@baderaqw]

Yooo so sad no one saw cosPeter and sinPeter :'( such an underappreciated joke

[@omegalord9432]

badoobido

[@zainh5397]

Badooooor

[@zainh5397]

@@omegalord9432 Abooooood

[@baderaqw]

@@zainh5397 yes abooooooooood

[@baderaqw]

@@omegalord9432 abeeeeeeeed

[@becks728]

15:49 how would you get the value of 1/sin theta if you didn’t do the triangle method ?

[@ymg1233]

Did you find out?

[@bythelord-2493]

Just draw the right angled triangle again then find sin using tan then do the inverse

[@StormoGFX]

you can solve it algebraically using identities for csc^2x: we want to use "1+cot^2x = csc^2x" •find cotx first: tanx = -2√2 (from part A) cotx = 1/tanx, so: cotx = 1/(-2√2) •find cot^2x by squaring both sides: cot^2x = 1/8 •therefore using the aforementioned identity "1+cot^2x = csc^2x": 1+cot^2x = 9/8 csc^2x = 9/8 •finally root both sides for cscx: cscx = (3√2)/4

[@pranav20op]

Broooo what a legend

[@aki-hb5vh]

very very juicy video teacher of Peter. I approve.

[@chelsea-wo7iy]

11:49 how do i know its only the negative value that works without using the cast diagram

[@zp6245]

If u look at the the tan graph between 90 and 180 as that's the range, the line would be under the x-axis meaning that it's negative.

[@IBRAHIM-jm7dh]

Great man u r the reason i passed

[@Fares-ps1yc]

Love you man!

[@Lukas-dz8sd]

you writing peter makes me go into depression

[@tarik_alk]

Trust

[@hsquar3d516]

14:56 , doesnt tan theta give you -1/3??

[@faugiamazumder5720]

Thank youuuuuuu

[@AliArif-yq5in]

Arigatōgozaimasu sir

[@ayaanhussain2853]

thank

[@the_crackin3610]

So crispy

[@wr7817]

18:15 couldn’t you have divided by 2 and gotten cos theta equals a half instead of having cos 2 theta

[@the_crackin3610]

Yes

[@steveafram1927]

It would give the wrong answers when using the cos graph to find the other solutions. Cos theta= 1/2 theta = 60 degrees So theta = 60 in the boundary of 0180. Seen on many Mark schemes with trigonometry questions, they increase the boundary by the coeffienct of theta/x. Finding the other solutions, them dividing them solutions by the coefficient for just theta, and any solutions outside the default boundary is not accepted. Hope this helps.

[@Ps-pn9qg]

Thank youuuu

[@bbalpha4921]

best

[@ayaanhussain2853]

you

[@tanniiekim2234]

Did he say juicy identities 💀

[@_doesnotexist]

u must be new here

[@zareenfarhatnawal2917]

Best