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D( a )
a = 0
a = 0
a = 0
a in (-oo:0) U (0:+oo)
63*a-((7/9)*a^-3) = 0
63*a+(-7/9)*a^-3 = 0
63*a^1-7/9*a^-3 = 0
(63*a^4-7/9*a^0)/(a^3) = 0 // * a^6
a^3*(63*a^4-7/9*a^0) = 0
a^3
63*a^4-7/9 = 0
63*a^4-7/9 = 0 // * 0
{ 1, -1, 7, -7 }
1
a = 1
567*a^4-7 = 560
1
-1
a = -1
567*a^4-7 = 560
-1
7
a = 7
567*a^4-7 = 1361360
7
-7
a = -7
567*a^4-7 = 1361360
-7
{ 1/3, -1/3, 1/7, -1/7, 1/9, -1/9, 1/21, -1/21, 1/27, -1/27, 1/63, -1/63, 1/81, -1/81, 1/189, -1/189, 1/567, -1/567, -1/3, 1/3, -1/7, 1/7, -1/9, 1/9, -1/21, 1/21, -1/27, 1/27, -1/63, 1/63, -1/81, 1/81, -1/189, 1/189, -1/567, 1/567, 7/3, -7/3, 7/7, -7/7, 7/9, -7/9, 7/21, -7/21, 7/27, -7/27, 7/63, -7/63, 7/81, -7/81, 7/189, -7/189, 7/567, -7/567, -7/3, 7/3, -7/7, 7/7, -7/9, 7/9, -7/21, 7/21, -7/27, 7/27, -7/63, 7/63, -7/81, 7/81, -7/189, 7/189, -7/567, 7/567 }
1/3
a
1/3
567*a^4-7 = 0
1/3
a-1/3
567*a^3+189*a^2+63*a+21
567*a^4-7
a-1/3
189*a^3-567*a^4
189*a^3-7
63*a^2-189*a^3
63*a^2-7
21*a-63*a^2
21*a-7
7-21*a
0
567*a^3+189*a^2+63*a+21 = 0
{ 1, -1, 3, -3, 7, -7, 21, -21 }
1
a = 1
567*a^3+189*a^2+63*a+21 = 840
1
-1
a = -1
567*a^3+189*a^2+63*a+21 = -420
-1
3
a = 3
567*a^3+189*a^2+63*a+21 = 17220
3
-3
a = -3
567*a^3+189*a^2+63*a+21 = -13776
-3
7
a = 7
567*a^3+189*a^2+63*a+21 = 204204
7
-7
a = -7
567*a^3+189*a^2+63*a+21 = -185640
-7
21
a = 21
567*a^3+189*a^2+63*a+21 = 5335680
21
-21
a = -21
567*a^3+189*a^2+63*a+21 = -5168940
-21
{ 1/3, -1/3, 1/7, -1/7, 1/9, -1/9, 1/21, -1/21, 1/27, -1/27, 1/63, -1/63, 1/81, -1/81, 1/189, -1/189, 1/567, -1/567, -1/3, 1/3, -1/7, 1/7, -1/9, 1/9, -1/21, 1/21, -1/27, 1/27, -1/63, 1/63, -1/81, 1/81, -1/189, 1/189, -1/567, 1/567, 3/3, -3/3, 3/7, -3/7, 3/9, -3/9, 3/21, -3/21, 3/27, -3/27, 3/63, -3/63, 3/81, -3/81, 3/189, -3/189, 3/567, -3/567, -3/3, 3/3, -3/7, 3/7, -3/9, 3/9, -3/21, 3/21, -3/27, 3/27, -3/63, 3/63, -3/81, 3/81, -3/189, 3/189, -3/567, 3/567, 7/3, -7/3, 7/7, -7/7, 7/9, -7/9, 7/21, -7/21, 7/27, -7/27, 7/63, -7/63, 7/81, -7/81, 7/189, -7/189, 7/567, -7/567, -7/3, 7/3, -7/7, 7/7, -7/9, 7/9, -7/21, 7/21, -7/27, 7/27, -7/63, 7/63, -7/81, 7/81, -7/189, 7/189, -7/567, 7/567, 21/3, -21/3, 21/7, -21/7, 21/9, -21/9, 21/21, -21/21, 21/27, -21/27, 21/63, -21/63, 21/81, -21/81, 21/189, -21/189, 21/567, -21/567, -21/3, 21/3, -21/7, 21/7, -21/9, 21/9, -21/21, 21/21, -21/27, 21/27, -21/63, 21/63, -21/81, 21/81, -21/189, 21/189, -21/567, 21/567 }
1/3
a
1/3
567*a^3+189*a^2+63*a+21 = 84
1/3
-1/3
a
-1/3
567*a^3+189*a^2+63*a+21 = 0
-1/3
a+1/3
567*a^2+63
567*a^3+189*a^2+63*a+21
a+1/3
-567*a^3-189*a^2
63*a+21
-63*a-21
0
567*a^2+63 = 0
DELTA = 0^2-(4*63*567)
DELTA = -142884
DELTA < 0
a in { 1/3, -1/3}
a in { 1/3, -1/3 }
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