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1 year ago

SOLVE x^4 − 15x^2 − 16 = 0 What are the roots of the equation?

Mathematics

1 answer:

kakasveta [241]1 year ago

8 0

Answer:

roots : 4, -4, i, -i

Step-by-step explanation:

This gets a bit tricky.

We have to substitude x^2 as u in this problem.

Now to rewrite x^4 − 15x^2 − 16 = 0 with u, we get

u^2 - 15u - 16 = 0

( u - 16) (u + 1)

U = 16

U = -1

<em>This is not the end of the problem. </em>

Now we have to substitute x^2 back to u.

x^2 = 16 --> we get the roots 4 and -4

x^2 = -1 --> we get the roots i and -i

tadah!

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2 years ago

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Answer:

The statements (1), (2), (4) and (6) are true.

Step-by-step explanation:

Consider the diagram below for the number line.

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Implying, √3 = √2 + 0.318.

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2 years ago

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