Step-by-step explanation:
I'm not sure about my answer
Answer:
10
Step-by-step explanation:
Answer:
f(x) and g(x) are closed under multiplication because when multiplied, the result will be a polynomial.
Step-by-step explanation:
The set of all polynomials is <em>closed</em> under addition, subtraction, and <em>multiplication</em>, because performing any of these operations on a pair of polynomials will give a polynomial result.
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<em>Comment on the question</em>
The wording is a bit strange, because f(x) and g(x) are elements of a set (of polynomials), so cannot be said to be "closed." "Closed" is a property of a set with respect to some function, it is not a property of an element of the set.
Write i in trigonometric form. Since |i| = 1 and arg(i) = π/2, we have
i = exp(i π/2) = cos(π/2) + i sin(π/2)
By DeMoivre's theorem,
i² = exp(i π/2)² = exp(i π) = cos(π) + i sin(π)
and it follows that i² = -1 since cos(π) = -1 and sin(π) = 0.