Write the solution set of the equation x2+x−2=0x^2 + x - 2 = 0 in roster form.

Answer: {1,−2}\{1, -2\}

Step-by-step solution

Step 1: Factor the quadratic equation

To find the solutions of the quadratic equation x2+x−2=0x^2 + x - 2 = 0, we can factor the quadratic expression. We look for two numbers that multiply to −2-2 and add up to 11. These numbers are 22 and −1-1. So, we can rewrite the middle term xx as 2x−x2x - x.

Step 2: Group terms and factor out common factors

Now, we group the terms and factor out the common factors from each pair. From the first two terms, x2+2xx^2 + 2x, we factor out xx. From the last two terms, −x−2-x - 2, we factor out −1-1. This gives us x(x+2)−1(x+2)=0x(x+2) - 1(x+2) = 0.

Step 3: Factor out the common binomial

We can see that (x+2)(x+2) is a common binomial factor in both terms. Factoring out (x+2)(x+2) leaves us with (x−1)(x+2)=0(x-1)(x+2) = 0.

Step 4: Solve for x

For the product of two factors to be zero, at least one of the factors must be zero. Therefore, we set each factor equal to zero and solve for xx. This gives us x−1=0x-1=0, which means x=1x=1, and x+2=0x+2=0, which means x=−2x=-2.

Step 5: Write the solution set in roster form

The solution set consists of all values of xx that satisfy the equation. In roster form, we list these values within curly braces. So, the solution set is {1,−2}\{1, -2\}.

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