Scroll to see replies
\\ \displaystyle \Re{\frac{e^{ni\theta}-1}{e^{i\theta}-1}}\\ =\Re{\frac{e^{\frac{ni\theta}{2}}(e^{\frac{ni \theta}{2}}-e^{\frac{-ni\theta}{2}})}{e^{\frac{i\theta}{2}}(e^{\frac{i \theta}{2}}-e^{\frac{-i\theta}{2}})}}\\ =\Re{(e^{(\frac{n-1}{2})i\theta}(\frac{2i\sin{\frac{n\theta}{2}}}{2i\sin{\frac{\theta}{2}}}))}\\ =\frac{\cos{(\frac{n-1}{2}\theta)}\sin{(\frac{n\theta}{2})}}{\sin{ (\frac{\theta}{2})}}}
Last reply 2 days ago
Did Cambridge maths students find maths and further maths a level very easy?Last reply 2 weeks ago
Edexcel A Level Mathematics Paper 2 unofficial mark scheme correct me if wrong71
Last reply 2 days ago
Did Cambridge maths students find maths and further maths a level very easy?Last reply 2 weeks ago
Edexcel A Level Mathematics Paper 2 unofficial mark scheme correct me if wrong71