Comments by "Fhf Fhf" (@fhffhff) on "Спасибо, послушаю" channel.

  1. 3/x=cos(2a),5/√(x²-9)=tga cos(2a)=(1-tg²a)/(1+tg²a) 3/x=(x² -14)/(x²-4) 0=(x-1)³-17(x-1)-4 x-1=(2+√(4-17³/27))¹/³+(..-..)..=2 (17/3)¹/²cos(1/3arccos(6/17√(3/ 17))+2/3πn) x=1+2(17/3)¹/²cos(1/ 3arccos(6/17√(3/17))+2/3πn)≥3 n=0 x=1+2(17/3)¹/²cos(1/3arccos (6/17√(3/17)))✓
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  2. h=-12+√319 h1=√319 a=9*2=18 S=-216+18√319✓
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  3. a²+9+6a*√(1-9/a²)=25 a=10⁰,⁵ x=√2
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