Trigonometric Identity Proof - example test question

[umapatil]

Do the students realise how lucky they are ?..(exited, polite tone)
I would be soo glad if I could attend his classes.

[haseebali]

Sir You are the best
You are great teacher of maths who makes maths a

[沈博智-xy]

8:24 the reciprocal trig functions are also on the reference sheet in the same heading as the Pythagorean identity "trigonometric identities"

[SteveHeller]

splitting the first fraction simplifies just as quickly! After all, it splits 1/sin from the left which matches the form on the right.

[nezzr]

I solved it like this:

(1 + cosQ) / sinQ + sinQ / (1 + cosQ) = 2cosecQ

LHS:
(1 + cosQ) / sinQ + sinQ / (1 + cosQ)

First change the second term a bit because (1 + cosQ) looks quite nice to work with.

(1 + cosQ) / sinQ + sinQ * (1 - cosQ) / ((1 + cosQ) * (1 - cosQ))

(1 + cosQ) / sinQ + sinQ * (1 - cosQ) / (1 - (cosQ)^2) --> identity: (sinQ)^2 = 1 - (cosQ)^2

(1 + cosQ) / sinQ + sinQ * (1 - cosQ) / (sinQ)^2 --> work on the fraction

(1 + cosQ) / sinQ + (1 - cosQ)/ sinQ --> Now we can put them both on the same nominator.

(1 + cosQ + 1 - cosQ) / sinQ

2/sinQ ---> Identity cosecQ = 1 / sinQ

2cosecQ = RHS

[elee]

Trig proofs...my fav 😍😍
They’re like puzzles

[_valon]

First view, like and comment. You’re inspiration!

[Nerdout]

I'm in 11th grade and studying maths but idk why these students are getting shocked with this trigonometry proof like our teacher never told us cross multifunction and fractions solving, this is understood. 😳

[Drforeverok]

Imagine if every teacher had ur ability, my goodness 😀

[atharvasharma]

Getting vibes of CBSE class 10 in India

[jcn]

im no where near college, but i learnt cos(0)+sin(0) is 1.

[vitaminprotein]

This is literally nothing for class 9 students in indian they are gonna solve this in just 30 seconds😂🙏

[johnryder]

A hideous mess transformed courtesy of Eddie