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Use the Wronskian to show that the functions f(x) = x² and g(x) = x³ are linearly independent.

User Slf
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Final answer:

The functions f(x) = x² and g(x) = x³ are shown to be linearly independent by computing their Wronskian, which does not vanish identically and therefore confirms their linear independence.

Step-by-step explanation:

To show that the functions f(x) = x² and g(x) = x³ are linearly independent using the Wronskian, we first need to compute the Wronskian determinant of f and g. The Wronskian W(f, g) is given by:

W(f, g) = | f(x) f'(x) |
| g(x) g'(x) |

Plugging the functions into the determinant, we get:

W(f, g) = | x² 2x |
| x³ 3x² |

Calculating the determinant, we have:

W(f, g) = x²(3x²) - x(2x) = 3x⁴ - 2x²

Simplifying this, we obtain:

W(f, g) = x²(3x² - 2)

Since the Wronskian is a function that does not vanish identically (it is not always zero for all x), we can conclude that f(x) = x² and g(x) = x³ are linearly independent functions.

User Zelig
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