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Factor by applying the sum of cubes.
Roots: x=-1, x= 1± isqrt(3)2
Number and Type of Roots: one real root, two imaginary roots
To solve the given equation, we will apply the sum of cubes. a^3+b^3 ⇔ (a+b)(a^2-ab+b^2) Let's start by factoring the left-hand side.
Write as a power
a^3+b^3=(a+b)(a^2-ab+b^2)
Identity Property of Multiplication
1^a=1
Use the Zero Product Property
(I): LHS-1=RHS-1
From Equation (I), we found that one root is x=- 1. To find other roots, we will solve Equation (II). Note that this is a quadratic equation. Thus, we will use the Quadratic Formula. ax^2+bx+c=0 ⇕ x=- b±sqrt(b^2-4ac)/2a To do so, we first need to identify a, b, and c. x^2-x+1=0 ⇕ 1x^2+( - 1)x+ 1=0 We see that a= 1, b= - 1, and c= 1. Let's substitute these values into the formula and evaluate the right-hand side. Remember that sqrt(- a)= isqrt(a).
Substitute values
- (- a)=a
Calculate power
Identity Property of Multiplication
Subtract term
sqrt(- a)= isqrt(a)
These roots of the quadratic equation are also roots of the given equation. Roots x=- 1, x=1 ± isqrt(3)/2 There are three roots. One of these roots is real and two of them are imaginary.