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Question Number 64686 by ajfour last updated on 20/Jul/19

Answered by ajfour last updated on 20/Jul/19

Let B be origin  and x axis along  BC.  x^2 +y^2 =c^2   (x−a)^2 +y^2 =b^2   ⇒  a(2x−a)=c^2 −b^2   x=((a^2 +c^2 −b^2 )/(2a))  y=(√(c^2 −(((a^2 +c^2 −b^2 )/(2a)))^2 ))  △^2 =((a^2 y^2 )/4) = (a^2 /4)[(((2ac−a^2 −c^2 +b^2 )(2ac+a^2 +c^2 −b^2 )/(4a^2 ))]      =(([b^2 −(a−c)^2 ][(a+c)^2 −b^2 ])/(16))  ⇒ 16△^2 =−(a^2 −c^2 )^2 −b^4 +2b^2 (a^2 +c^2 )       = −a^4 −b^4 −c^4 +2(a^2 c^2 +b^2 c^2 +c^2 a^2 )       =2Σa^2 b^2 −Σa^4        =4Σa^2 b^2 −(Σa^2 )^2        =4Σa^2 b^2 −[(a+b+c)^2 −2Σab]^2        =4Σa^2 b^2 −[16s^4 −16s^2 Σab+4(Σab)^2 ]       =−16s^4 +16s^2 Σab−16(abc)s  ⇒ △=(√(s^2 Σab−s^4 −(abc)s))   △=(√(s[s(ab+bc+ca)−s^3 −abc]))       =(√(s[s(ab+bc+ca)+s^3 −s(a+b+c)−abc))  ⇒   __________________________    △=(√(s(s−a)(s−b)(s−c)))    __________________________

LetBbeoriginandxaxisalongBC.x2+y2=c2(xa)2+y2=b2a(2xa)=c2b2x=a2+c2b22ay=c2(a2+c2b22a)22=a2y24=a24[(2aca2c2+b2)(2ac+a2+c2b24a2]=[b2(ac)2][(a+c)2b2]16162=(a2c2)2b4+2b2(a2+c2)=a4b4c4+2(a2c2+b2c2+c2a2)=2Σa2b2Σa4=4Σa2b2(Σa2)2=4Σa2b2[(a+b+c)22Σab]2=4Σa2b2[16s416s2Σab+4(Σab)2]=16s4+16s2Σab16(abc)s=s2Σabs4(abc)s=s[s(ab+bc+ca)s3abc]=s[s(ab+bc+ca)+s3s(a+b+c)abc__________________________=s(sa)(sb)(sc)__________________________

Commented by mr W last updated on 20/Jul/19

what′s the question sir?

whatsthequestionsir?

Commented by ajfour last updated on 20/Jul/19

Nothing Sir, just whiling away  my time.  (^⌢_•  ∣^(  ⌢_• ) _⌣ ∂

NothingSir,justwhilingawaymytime.(

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