WEBVTT
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What are the zeros of π of π₯ equal to π₯ plus π squared minus π?
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First, we copy down our problem.
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And then in place of π of π₯, we want to put a zero.
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Weβre looking for the place where π of π₯ is equal to zero.
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And then, we can solve this using algebra.
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Weβre trying to isolate π₯, get π₯ by itself.
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The first thing I can do is get rid of the π by adding π to the right side of the equation.
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If we add π to the right, we have to add π to the left.
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Negative π plus π equals zero.
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Zero plus π equals π.
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Our equation now says π is equal to π₯ plus π squared.
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To get rid of the square, we take the square root of π₯ plus π squared.
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But if we take the square root on the right, we need to take the square root on the left.
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On the right side of the equation, the only thing that remains is π₯ plus π.
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The left side is a little bit different.
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On the left side, we need to say that we have two options: we have the positive square root of π and the negative square root of π.
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We have two cases.
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There is no reason for our parentheses anymore.
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So we can drop those and then we subtract π from both sides of the equation.
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Positive π minus π equals zero.
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π₯ is by itself on the right side.
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On the left side, there is nothing really that we can simplify.
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We can just say negative π plus or minus the square root of π.
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And this is how we break that down into two different options: π₯ could be equal to negative π plus π or negative π minus the square root of π.
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This function has two zeros: negative π plus the square root of π and negative π minus the square root of π.