помогите решить sin20*sin50*sin70*/sin80*. Created by AlvaroMaybach. algebra-ru

sin80*...

AlvaroMaybach @AlvaroMaybach

July 2022 1 19 Report

помогите решить sin20*sin50*sin70*/sin80*

Answers & Comments

kirichekov

Verified answer

Sin20*sin50*sin79/sin80=0,25

1. sin20*sin70*sin50=sin20*sin(90-20)*sin50=sin20*cos20*sin50=(1/2)*(2sin20cos20)*sin50=0,5/sin40*sin50

2. sin80=sin(2*40)=2sin40*cos40=2sin40*cos(90-50)=2sin40*sin50

3. (0,5*sin40*cos50) / (2sin40*cos50)=0,5/2=0,25

3 votes Thanks 4

kirichekov в 1-м действии опечатка, ответ: 0,5*sin40*sin50

Answers & Comments

Verified answer

Helpful Links

Helpful Social