Let y=ax3+bx2+cx+d. Then
y′=3ax2+2bx+c
y′′=6ax+2b Substitute
(1−x2)(6ax+2b)−2x(3ax2+2bx+c)
+12(ax3+bx2+cx+d)=0
(−6a−6a+12a)x3+(−2b−4b+12b)x2
+(6a−2c+12c)x+2b+12d=0 x3:0=0
x2:6b=0
x1:6a+10c=0
x0:2b+12d=0
c=−53a,b=0,d=0
y=ax3−53ax,a∈R
One of the solutiin of the given equation is
y=5x3−3x
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