# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a199620 Showing 1-1 of 1 %I A199620 #5 Mar 30 2012 18:57:58 %S A199620 3,4,5,2,8,9,9,8,8,8,5,3,2,9,2,7,7,8,0,3,3,6,3,0,0,8,3,7,8,6,4,9,8,3, %T A199620 8,8,4,0,8,8,3,6,8,5,5,6,5,7,8,5,1,5,3,8,6,4,0,5,6,2,7,2,9,0,9,5,5,1, %U A199620 8,5,6,4,0,8,5,9,2,4,4,5,4,6,8,3,0,5,7,0,2,5,8,4,9,8,6,0,9,6,0 %N A199620 Decimal expansion of greatest x satisfying x^2+4*x*cos(x)=4*sin(x). %C A199620 See A199597 for a guide to related sequences. The Mathematica program includes a graph. %e A199620 least: 0.80005334262741575936859027990893321963... %e A199620 greatest: 3.4528998885329277803363008378649838... %t A199620 a = 1; b = 4; c = 4; %t A199620 f[x_] := a*x^2 + b*x*Cos[x]; g[x_] := c*Sin[x] %t A199620 Plot[{f[x], g[x]}, {x, -.5, 4}, {AxesOrigin -> {0, 0}}] %t A199620 r = x /. FindRoot[f[x] == g[x], {x, .8, .81}, WorkingPrecision -> 110] %t A199620 RealDigits[r] (* A199619, least pos root *) %t A199620 r = x /. FindRoot[f[x] == g[x], {x, 3.4, 3.5}, WorkingPrecision -> 110] %t A199620 RealDigits[r] (* A199620, greatest of 3 roots *) %Y A199620 Cf. A199597. %K A199620 nonn,cons %O A199620 1,1 %A A199620 _Clark Kimberling_, Nov 08 2011 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE