Saturday, January 12, 2019

$\def\D{\displaystyle}$
1 (Edexcel, Further Pure Math, 2013 jan, Paper 2, No 2)
Using the identities $\D
\sin (A + B) = \sin A \cos B + \cos A \sin B \\
\cos (A + B) = \cos A \cos B – \sin A \sin B \\
\tan A=\D\frac{\sin A}{\cos A} $
(a) show that $\D \tan(A+B)=\frac{\tan A+\tan B}{1-\tan A\tan B}$ (3)
(b) Hence show that
(i) $\D \tan 105^{\circ}=\frac{1+\sqrt{3}}{1-\sqrt{3}}$
(ii) $\D \tan 15^{\circ}=\frac{\sqrt{3}-1}{1+\sqrt{3}}$ (4)

4 comments:

  1. This is such a great resource that you are providing and you give it away for free. I love seeing blog that understand the value of providing a quality resource for free. footcare drill

    ReplyDelete
  2. This is such a great resource that you are providing and you give it away for free. I love seeing blog that understand the value of providing a quality resource for free. chiropodists drills

    ReplyDelete
  3. This particular papers fabulous, and My spouse and i enjoy each of the perform that you have placed into this. I’m sure that you will be making a really useful place. I has been additionally pleased. Good perform! Impact Wrench Guides

    ReplyDelete