Question Number 199952 by Abdullahrussell last updated on 11/Nov/23
Answered by cortano12 last updated on 11/Nov/23
$$\:=\:\frac{\mathrm{2sin}\:\mathrm{7}\theta\:\mathrm{cos}\:\mathrm{2}\theta\:+\:\mathrm{2sin}\:\mathrm{7}\theta\:\mathrm{cos}\:\mathrm{6}\theta}{\mathrm{2cos}\:\mathrm{7}\theta\:\mathrm{cos}\:\mathrm{2}\theta\:+\:\mathrm{2cos}\:\mathrm{7}\theta\:\mathrm{cos}\:\mathrm{6}\theta} \\ $$$$\:=\:\frac{\mathrm{sin}\:\mathrm{7}\theta\left(\mathrm{cos}\:\mathrm{2}\theta+\mathrm{cos}\:\mathrm{6}\theta\right)}{\mathrm{cos}\:\mathrm{7}\theta\left(\mathrm{cos}\:\mathrm{2}\theta+\mathrm{cos}\:\mathrm{6}\theta\right)} \\ $$$$\:=\:\mathrm{tan}\:\mathrm{7}\theta \\ $$