SOLUTION: Find the largest possible domain of y=ln(sin inverse x)

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Question 1142691: Find the largest possible domain of y=ln(sin inverse x)

Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
the largest domain of y = arcsin(x) appears to be 0 < x <= 1.

y = sin(x) gives you a value of y = -1 to 1.

that's the range of y = sin(x).

y = arcsin(-1) = -90 degrees.
y = arcsin(1) = 90 degrees.

the value of x goes from -1 to 1 and the value of y goes from -90 degrees to 90 degrees.

the domain of y = arcsin(x) is -1 <= x <= 1.

the domain of y = ln(arcsin(x)) is 0 < x <= 1.

that's because the natural log of a number requires the number to be greater than 0.

since arsin(0) = 0, that would be invalid.
as long as arcsin(x) has x > 0, then the value would be valid.

i think this is what you are looking for.

the domain would be 0 <= x <= 1
the range would be -infinity < y <= ln(90) when working with degrees.
since 90 degrees * pi / 180 = pi/2 radians, then the range would be -infinity to pi/2 radians when working with radians.

whether working with degrees or radians, the domain is still 0 < x <= 1.

the following graphs illustrate this.

the first 2 graphs show the value of y in degrees.

the last 2 graphs shosw the value of y in radians.

in both cases, the value of ln(arcsin(x)) has a domain of 0 < x <= 1.

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i'm not exactly sure that this is what you're looking for, but it's what i get based on my interpretation of the problem.