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4 votes
Please, What is the answer?

Please, What is the answer?-example-1

2 Answers

3 votes
X = -2 because is a root
User Psur
by
4.6k points
11 votes

Answer: You have the correct answer. It's choice A.

Step-by-step explanation:

You can verify this by plugging each root into the equation.

So for instance, plug in x = -2 and we get

f(x) = -3*(x+2)*(x-sqrt(3))*(x-4)

f(-2) = -3*(-2+2)*(-2-sqrt(3))*(-2-4)

f(-2) = -3*(0)*(-2-sqrt(3))*(-2-4)

f(-2) = 0

This verifies x = -2 is a root.

All that matters is that zero buried in there in the second to last step. Multiplying 0 by anything leads to 0. The other roots are verified in the same manner. The -3 out front is the leading coefficient.

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Extra info:

  • Choice B is eliminated because (x+3) being a factor implies that x = -3 is a root. But this isn't listed in the instructions.
  • Choice C is a similar story to choice B
  • Choice D is eliminated since -sqrt(3) is not one of the listed roots, so (x+sqrt(3)) is not a factor.
User Sasuri
by
5.8k points
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