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What are the solutions of the equation 9x4 – 2x2 – 7 = 0? Use u substitution to solve.x = + √7/9 and x = ±1 x = + √7/9 and x = ±i x = +i √7/9 and x = ±1 x = +i √7/9 and x = ±I 

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Answer:

Step-by-step explanation:

9x⁴ – 2x² – 7 = 0

Let's say that u = x²:

9u² – 2u – 7 = 0

Factor:

(u – 1) (9u + 7) = 0

u = 1, -7/9

Since u = x²:

x² = 1, -7/9

x = ±1, ±i √(7/9)

Lanuel

By using the substitution method, the solutions of this equation (polynomial) is equal to C. x = ±1 and ±i√(7/9).

How to determine the solutions of an equation?

In order to determine the solutions of this equation (polynomial), we would let "u" be equal to x² and then substitute this value into the equation as follows:

9x⁴ - 2x² - 7 = 0

Substituting the value of "u" into the equation (polynomial), we have:

9u² - 2u - 7 = 0

Factorizing the equation (polynomial), we have:

(9u + 7)(u - 1) = 0

u = 1 and -7/9

Since, u = x²:

x² = 1 and -7/9

x = ±√(1 and -7/9)

x = ±1 and ±i√(7/9).

Read more on polynomials here: https://brainly.com/question/1600696

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