Если синий карандаш толще красного, а красный толще голубого, то какой карандаш толще: голубой или синий?

2ydy=-2xdx=>y^2=C-x^2=>y=\pm \sqrt{C-x^2}" class="latex-formula" id="TexFormula2" src="https://tex.z-dn.net/?f=yy%27%3D-x%3D%3E2ydy%3D-2xdx%3D%3Ey%5E2%3DC-x%5E2%3D%3Ey%3D%5Cpm%20%5Csqrt%7BC-x%5E2%7D" title="yy'=-x=>2ydy=-2xdx=>y^2=C-x^2=>y=\pm \sqrt{C-x^2}">

y'=\\ u+xu'\right]\\ xu(u+xu')=2xu-x\\ xu'=2-\dfrac{1}{u}-u\\ \int\dfrac{-udu}{(u-1)^2}=\int\dfrac{dx}{x}\\ -\int\dfrac{((u-1)+1)du}{(u-1)^2}=lnCx\\ \int\dfrac{du}{(u-1)}+\int\dfrac{du}{(u-1)^2}=-lnCx\\ ln(u-1)-\dfrac{1}{u-1}=-lnCx\\ ln(\dfrac{y}{x}-1)-\dfrac{x}{y-x}=-lnCx" class="latex-formula" id="TexFormula4" src="https://tex.z-dn.net/?f=yy%27%3D2y-x%5C%5C%20%5Cleft%5By%3Dx%2Au%28x%29%3D%3Ey%27%3D%5C%5C%20u%2Bxu%27%5Cright%5D%5C%5C%20xu%28u%2Bxu%27%29%3D2xu-x%5C%5C%20xu%27%3D2-%5Cdfrac%7B1%7D%7Bu%7D-u%5C%5C%20%5Cint%5Cdfrac%7B-udu%7D%7B%28u-1%29%5E2%7D%3D%5Cint%5Cdfrac%7Bdx%7D%7Bx%7D%5C%5C%20-%5Cint%5Cdfrac%7B%28%28u-1%29%2B1%29du%7D%7B%28u-1%29%5E2%7D%3DlnCx%5C%5C%20%5Cint%5Cdfrac%7Bdu%7D%7B%28u-1%29%7D%2B%5Cint%5Cdfrac%7Bdu%7D%7B%28u-1%29%5E2%7D%3D-lnCx%5C%5C%20ln%28u-1%29-%5Cdfrac%7B1%7D%7Bu-1%7D%3D-lnCx%5C%5C%20ln%28%5Cdfrac%7By%7D%7Bx%7D-1%29-%5Cdfrac%7Bx%7D%7By-x%7D%3D-lnCx" title="yy'=2y-x\\ \left[y=x*u(x)=>y'=\\ u+xu'\right]\\ xu(u+xu')=2xu-x\\ xu'=2-\dfrac{1}{u}-u\\ \int\dfrac{-udu}{(u-1)^2}=\int\dfrac{dx}{x}\\ -\int\dfrac{((u-1)+1)du}{(u-1)^2}=lnCx\\ \int\dfrac{du}{(u-1)}+\int\dfrac{du}{(u-1)^2}=-lnCx\\ ln(u-1)-\dfrac{1}{u-1}=-lnCx\\ ln(\dfrac{y}{x}-1)-\dfrac{x}{y-x}=-lnCx">