分からない問題はここに書いてね458

前>>564
P(p,p^2),O(0,0),Dのx切片(0,b^2+c)を結ぶ領域αがまだだけど、
E=-10b/9c+20/27c-4/27c^3+c^3/3-2c/3-b^3/3-α
F=-4c^3/3-bc/3+7c/9+b/c-20/27c+4/27c^3+b^3/3+α
F-E=-4c^3/3-bc/3+7c/9+b/c-20/27c+4/27c^3+b^3/3+α-(-10b/9c+20/27c-4/27c^3+c^3/3-2c/3-b^3/3-α)
=-4c^3/3-bc/3+7c/9+b/c-20/27c+4/27c^3+b^3/3+α+10b/9c-20/27c+4/27c^3-c^3/3+2c/3+b^3/3+α
=-4c^3/3-bc/3+7c/9+19b/9c-20/27c+8/27c^3+2b^3/3-20/27c-c^3/3+2c/3+2α
=-5c^3/3-bc/3+13c/9+19b/9c-40/27c+8/27c^3+2b^3/3+2α
=-5c^3/3-bc/3+13c/9+19b/9c-40/27c+8/27c^3+2b^3/3+2α