Find-the-value-of-4-sin-pi-24-cos-pi-12-cos-pi-6- Tinku Tara June 4, 2023 Trigonometry 0 Comments FacebookTweetPin Question Number 17435 by 786786AM last updated on 06/Jul/17 Findthevalueof4sinπ24cosπ12cosπ6. Answered by alex041103 last updated on 07/Jul/17 LetA=4sinπ24cosπ12cosπ6.Thenweusesin2θ=2sinθcosθ:A=2(2sinπ24cosπ24)cosπ12cosπ61cosπ24=(2sinπ12cosπ12)cosπ61cosπ24=12cosπ24(2sinπ6cosπ6)=sinπ32cosπ24Weknowthatcos2θ=2cos2θ−1⇒cos2θ2=1+cosθ2Whenθ∈[0,π2],θ2∈[0,π2]⇒cosθ2≧0⇒cosθ2=1+cosθ2Fromthiswecanevaluatecosπ24cosπ12=1+cosπ62=1+322=2+34=2+32cosπ24=1+cosπ122=1+2+322=2+2+34=2+2+32AndnowwesolveforA:A=3222+2+32=322+2+3A=1232+2+3A=4sinπ24cosπ12cosπ6=1232+2+3≈0.436749… Commented by mrW1 last updated on 07/Jul/17 verygoodsir! Commented by alex041103 last updated on 07/Jul/17 CanyouseemyanswertoQ:17514.I′llposttheholeproveatsomepoint. Terms of Service Privacy Policy Contact: info@tinkutara.com FacebookTweetPin Post navigation Previous Previous post: 1-find-dx-x-2-x-1-6-2-calculate-dx-x-2-x-1-6-Next Next post: calculate-lim-n-0-n-1-x-n-n-arctan-nx-dx- Leave a Reply Cancel replyYour email address will not be published. Required fields are marked *Comment * Name * Save my name, email, and website in this browser for the next time I comment.