WEBVTT
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to find the domain of this function. Let's concentrate
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on the quantity inside the square root. We need
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that quantity to be greater than or equal to zero
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because that's the only way to get a really output
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. So we need 10 to the power t minus
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100 to be greater than or equal to zero.
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So 10 to the power T is going to be
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greater than or equal to 100. Okay, we
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know that 10 to the second power is 100.
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So if t is greater than or equal to two
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, we ought to have numbers that will fit in
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the domain and will give us a real output.
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And if we want to put if we want to
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give this answer using interval notation, we can say
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to to infinity Now, for part B, we
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want to find the domain of this function. So
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if you think about it, the sine function in
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General Weichel sign of X has the domain, all
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real numbers. So it really doesn't matter what you
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end up getting for each of the T minus one
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. Because no matter what it is, it's going
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to be the sign of it is going to be
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riel and e to the T always gives you a
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real output. Subtracting one from that always gives you
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a real output on the sign of a real numbers
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. A real number. So there are no restrictions
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to the domain. The domain is going to be
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all real numbers, and you can write that as
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negative infinity to infinity.