To solve the binomial equation, we'll apply the formula of
the sum of cubes:
a^3 + b^3 = (a+b)(a^2 - ab +
b^2)
a^3 = 64x^3
a =
4x
b^3 = 11^3
b =
11
64x^3+1331 = (4x+11)(16x^2 - 44x +
121)
If 64x^3+1331 = 0, then (4x+11)(16x^2 - 44x + 121) =
0
If a product is zero, then each factor could be
zero.
4x+11 = 0
We'll
subtract 11 both sides:
4x =
-11
x1 = -11/4
16x^2 - 44x +
121 = 0
We'll apply the quadratic
formula:
x2 = [44 +
sqrt(1936-7744)]/2
x2 =
(44+44isqrt3)/32
We'll factorize by 44 the
numerator:
x2 =
44(1+isqrt3)/32
x2 =
11(1+isqrt3)/8
x3 =
11(1-isqrt3)/8
The roots of the equation are:
{-11/4 , 11(1-isqrt3)/8, 11(1+isqrt3)/8 }.
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