Comments by "Fhf Fhf" (@fhffhff) on "Дмитрий Гордон" channel.

  1. a+9,2a-3 4,a-2,a-1 A+5,a+1,a a+9+a+5=2a-3+a-1+a -2a=-16 a=8. ?=17² =289.
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  2. (S+45)/(S+105),(S+35)/(S+105),S/(S+105) (S+45)(S+35)/(S+105)²=S/(S+10 5) S²+80S+45*35=S²+105S -25S=-45*35 S=9*7=63 ?=63+15=78.
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  3. {х²+Ху+у²=529,х²+√3xz+z²=441,x²+y²=144;{х=-0,5y±√(-0,75у²+529), (-0,5y±√(-0,75 y²+529))²+√3(-0,5y±√(-0,75y²+529))z+z²=441, y⁴+144y²-385²=0;y=±(√(457/2)±√(3 13/2)){x=-+(0,5√228,5±0,5√156,5)±√(-+ 0,75√(457*313)+240,25),z=-0,5√3(-+(0,5 √228,5±0,5√156,5)±√(-+ 0,75√(457*313 )+240,25))±√(356,875±0,125√(457*313) +(0,25√228,5±0,25√156,5)√(-+0,75√(457*313)))
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  4. q=BCtg(/_B/2) p=AB/2/cos(/_B-90°) pq=AB*BC/4/cos²(0,5/_B) R=BC/2/sin/_A sin/_C=sin/_Acos²/_C+2cos/_Asin/_Ccos/_C+cos²/_Asin²/_C/sin/_A ч.т.д.
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  5. o(0;45°) √(36+l²-12lcoso),√(9+l²-6lc os(3o)) √2*sin(3o)√(5+sin(6o)-2sin(4o)-2s in(2o)-2cos(4o)-2cos(2o))=-0,5+sin(2o)+cos(2o)+sin(4o)-cos(4o)+0,5 cos(6o)-0,5sin(6o),3cos(3o)+3sin3 o=l,l≥3cos(3o) 2*sin²(3o)(5+sin(6o)-2sin(4o)-2sin (2o)-2cos(4o)-2cos(2o))=(-0,5+sin(2o)+cos(2o)+sin(4o)-cos(4o)+0,5 cos(6o)-0,5sin(6o))² o=15,3°;28,7°✓
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  6. (π/6-0,5)/0,5=π/3-1=0,047!!?
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  7. 484/(1934*49+6)=0,005 !
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  8. S=12,5arcsin(4/5)-6
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  9. 7920руб.
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  10. y''+(1-2/t)y'+y/t=0 (u'+0,5-1/t)'+(u'+0,5-1/t)²=0,25-2/t+2/t² (u'+0,5-1/t)-¹/-1+t=c u'+0,5-1/t=1/(t-c) ..=c1t-¹+c2 -c1t-²+c1²t-² +2c1c2t-¹+c2²=2/t²-2/t+0,25{[c1=2, c1=-1; c1=-+2,c2=±0,5;{c1=2,c2=-0,5; u'+0,5-1/t=2t-¹-0,5 [u=-0,5t+ln|t|+ln|t-c|+c1,u=-t+3ln|t|+c1;[y=e^(-0,5t)t(t-c)c1, y=e^(-t)t³c1.
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