Х/2-1/4:3=х/8+1/2:9-9
х/2-1/12=х/8+1/18-9
х/2-х/8=1/12+1/18-9
3х/8=3+2-324/36
3х/8=-319/36
х=-319/36*8/3
х=-1276/27
4 исхода, благоприятствующих событию
1+4
4+1
2+3
3+2
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<span>sin(30°-α)+sin(30°+α)=cosα</span>
<span><span>sin(pi/6 -α)+sin(pi/6+α)=cosα</span></span>
<span><span>(sin(pi/6)*cosα-cos(pi/6)*sinα)+(sin(pi/6)*cosα+cos(pi/6)*sinα)=cosα</span></span>
<span><span>sin(pi/6)*cosα+sin(pi/6)*cosα=cosα</span></span>
<span><span>2sin(pi/6)*cosα=cosα</span></span>
<span><span>2*1/2*cosα=cosα</span></span>
<span><span>cosα=cosα</span></span>
α=(-∞;+∞)
Ответ:α=R