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Identify all of the root(s) of g(x) = (x2 - 3x - 4)(x2 - 4x + 29).
Solution:
Given: Function g(x) = (x2 - 3x - 4)(x2 - 4x + 29)
Let us first consider x2 - 3x - 4
= x2 + 1x - 4x - 4
= x(x + 1) - 4(x + 1)
= (x + 1)(x - 4)
Now let us consider x2 - 4x + 29
First group the terms with variable on LHS and move the constant on the other side
x2 - 4x = -29
Add 4 on both sides
x2 - 4x + 4 = -29 + 4
x2 - 4x + 4 = -25
It can be written as perfect squares
(x - 2)2 = -25
We know that
i =√1
Take square root on both sides
x - 2 = ± 5i
x = 2 ± 5i
So we get,
x = 2 + 5i and x = 2 - 5i
g(x) = (x + 1)(x - 4)(2 + 5i)(2 - 5i)
Therefore, the roots are (x + 1), (x - 4), (2 + 5i), and (2 - 5i).
Identify all of the root(s) of g(x) = (x2 - 3x - 4)(x2 - 4x + 29).
Summary:
All the root(s) of g(x) = (x2 - 3x - 4)(x2 - 4x + 29) are (x + 1), (x - 4), (2 + 5i), and (2 - 5i).
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