T-result question (1 Viewer)

[Aysce]

Prove Tan A - Tan A/2 = Tan A/2 x Sec A

where t= Tan A/2

Thank you

 

[Alkanes]

Is RHS = Tan A/2 x Sec A ?

 

[Aysce]

Yeah I'll edit it sorry.

 

[Alkanes]

Sorry i cannot be bothered with latex. Spiral will do this for me later

LHS = Tan A - Tan A/2
= 2t/1-t^2 - t
= 2t - t + t^3 / 1-t^2
= t^3 + t /1-t^2
= t(1+t^2)/1-t^2
=
RHS = Tan A/2 x Sec A
= t x (1+t^2/1-t^2)
= t+t^3/1-t^2
= t(1+t^2)/1-t^2

LHS = RHS

 

[Alkanes]

For this question you needa prove from both sides i believe.

 

[Drongoski]

where .A stands for A/2



Note

should use tan rather than Tan.

 

[Aysce]

where .A stands for A/2



Note

should use tan rather than Tan.

Thanks for the help but I kinda forgot, why does, on the LHS, tanA = 2tan.A?

 

[blackops23]

where .A stands for A/2



Note

should use tan rather than Tan.

impressive solution drongoski, my one was at least 3-4 times the length of your solution...