WEBVTT
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Consider the function π of π₯ equals π₯ squared minus three π₯ minus four.
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Find π of π₯ plus three.
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In order to find π of π₯ plus three, we need to replace all of the π₯s with π₯ plus three.
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So essentially, weβre replacing π₯ with π₯ plus three and then evaluating.
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So here we can see weβve replaced π₯ with π₯ plus three.
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And now we need to evaluate this.
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π₯ plus three squared is π₯ plus three times π₯ plus three.
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And then we also need to distribute the negative three to the π₯ plus three in the middle.
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π₯ times π₯ is π₯ squared.
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π₯ times three is three π₯.
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Three times π₯ is three π₯.
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And three times three is nine.
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And now we will distribute negative three to π₯ plus three.
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Negative three times π₯ is negative three π₯.
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And negative three times three is negative nine.
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And then we bring down our minus four.
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So now we need to combine like terms.
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Our highest power is two.
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So π₯ squared needs to go first.
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Now we can combine all of the π₯s.
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Three π₯ plus three π₯ minus three π₯ is three π₯.
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And now for the numbers, the constants, nine, negative nine, and negative four make negative four.
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Therefore, π of π₯ plus three is equal to π₯ squared plus three π₯ minus four.