Find the real or imaginary solutions of the following equation by factoring.

x^3+343=0

1 answer

We can rewrite the equation as:

(x)^3 + (7)^3 = 0

We can use the sum of cubes formula, which states that: a^3 + b^3 = (a + b)(a^2 - ab + b^2)

So, applying this formula to our equation, we have:

(x + 7)(x^2 - 7x + 7^2) = 0

Now, we can solve for x in each factor:

x + 7 = 0 -> x = -7

x^2 - 7x + 49 = 0

Using the quadratic formula, x = ( -(-7) ± √( (-7)^2 - 4(1)(49) ) ) / (2(1))
Simplifying further, we have x = (7 ± √(-147)) / 2

Since we have a negative value under the square root, the solutions are imaginary.

Thus, the solutions to the equation x^3 + 343 = 0 are -7 and (7 ± √(-147)) / 2.