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Please solve and show steps

Please solve and show steps-example-1

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Answer:

Explanation:

There are 6 solutions or zeros here because, according to the Fundamental Theorem of Algebra, the degree of the polynomial dictates how many zeros there are in the polynomial. If we had a 3rd degree polynomial, we would expect to find 3 zeros; if we had a 5th degree polynomial, we would have 5 zeros, etc. The easiest way to factor this is to do it initially by grouping:


(4x^6+20x^4)-(25x^2-125) then


4x^4(x^2+5)-25(x^2+5) then


(x^2+5)(4x^4-25)=0

We will factor each set of parenthesis now to get all the zeros. For the first set of parenthesis:


x^2+5=0 so


x^2=-5 so


x=√(-5)

But since we can't have a negative under the square root, we have to offset it by using the imaginary number i. i-squared = -1, so

x = ±i√5

Those are the first 2 zeros out of 6. Now for the second set of parenthesis:

4x⁴ - 25 = 0. That is the difference between perfect squares, and that factors to this:

(2x² + 5)(2x² - 5)

The first set of parenthesis there:

2x² + 5 = 0 so

2x² = -5 so

x² = -5/2 so

x = ±
\sqrt{(5)/(2) }i

Those are the next 2 zeros. We found 4 so far, now we will find the last 2 in the second set of parenthesis above:


x^2-5=0 so


x^2=5 so

x = ±
\sqrt{(5)/(2) }

In summary, the 6 zeros are as follows:

x =
√(5)i, -
√(5)i,
\sqrt{(5)/(2) }i,
-\sqrt{(5)/(2) }i,
\sqrt{(5)/(2) },
-\sqrt{(5)/(2) }

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