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Create and solve by completing the square a quadratic equation with no, 1 , and 2 solutions real solutions. Explain all your steps as if your were teaching a friend.

User Zack Katz
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1 Answer

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Answer:

The three quadratic equations are;

x² + 3 = 0

x² + 2·x + 1 = 0

x² + 3·x + 2 = 0

Explanation:

1) A quadratic equation with no real solution is one with an imaginary solution such as one with a negative square root

We can write the quadratic equation as follows;

x² + 3 = 0

∴ x = √(-3) = √(-1) ×√3 = i·√(3)

Therefore, the equation f(x) = x² + 3, has no real root at f(x) = 0

2) A quadratic that has 1 real root is of the form;

(x + 1)² = 0

The root of the equation is x = -1 from (x + 1) = ((-1) + 1)² = 0²

Which gives;

(x + 1)² = (x + 1)·(x + 1) = x² + 2·x + 1 = 0

Therefore, the quadratic (x + 1)² = 0 has only one real root

3) A quadratic that has 2 real root is of the form;

(x + 1)·(x + 2) = 0

x² + x + 2·x + 2 = 0

x² + 3·x + 2 = 0

Therefore, the three quadratic equations are;

x² + 3 = 0

x² + 2·x + 1 = 0

x² + 3·x + 2 = 0

User Anupam Basak
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5.6k points