Question and Answers Forum

All Questions      Topic List

Trigonometry Questions

Previous in All Question      Next in All Question      

Previous in Trigonometry      Next in Trigonometry      

Question Number 199718 by cortano12 last updated on 08/Nov/23

$$\{\begin{array}{l}\cos \mathrm{x}+\cos \mathrm{y}=\frac{1}{2}\\ \sin \mathrm{x}+\sin \mathrm{y}=\frac{1}{4}\\ \sin 2\mathrm{x}+\sin 2\mathrm{y}=-\frac{27}{20}\end{array}$$$$\sin (\mathrm{x}+\mathrm{y})=...$$

Answered by Sutrisno last updated on 08/Nov/23

$$(cosx+cosy)(sinx+siny)=\frac{1}{8}$$$$cosxsinx+cosxsiny+cosysinx+cosysiny=\frac{1}{8}$$$$\frac{1}{2}sin2x+sin(x+y)+\frac{1}{2}sin2y=\frac{1}{8}$$$$\frac{1}{2}(sin2x+sin2y)+sin(x+y)=\frac{1}{8}$$$$\frac{1}{2}\left(\frac{-27}{20}\right)+sin(x+y)=\frac{1}{8}$$$$sin(x+y)=\frac{1}{8}+\frac{27}{40}$$$$sin(x+y)=\frac{32}{40}$$$$$$

Terms of Service

Privacy Policy

Contact: info@tinkutara.com