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Are sin(x) and ex linearly independent? Justify.

User Chevybow
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Final answer:

Sin(x) and e^x are linearly independent because their Wronskian is never zero; sin(x) and cos(x) are not multiples of each other, and e^x is never zero.

Step-by-step explanation:

To determine if the functions sin(x) and ex are linearly independent, we can employ the Wronskian test.

Two functions f and g are linearly independent if their Wronskian, W(f, g) = f(x)g'(x) - g(x)f'(x), is nonzero for at least one point in the interval being considered.

To apply the Wronskian to sin(x) and ex, we calculate:

f(x) = sin(x)

g(x) = ex

f'(x) = cos(x)

g'(x) = ex

W(sin(x), ex) = sin(x) x (ex) - ex x cos(x)

Since ex is never zero and sin(x) and cos(x) are not multiples of each other, the Wronskian is never zero. Therefore, sin(x) and ex are linearly independent functions.

User Neverland
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