document.write( "Question 1197653: Which if the following functions has domain (-1,1)and range (0,pi)
\n" ); document.write( "A. f(x)=sin((pi/2)x)
\n" ); document.write( "B. f(x)=arcsin(x)
\n" ); document.write( "C. f(x)=cos(x)
\n" ); document.write( "D. f(x)=arccos(x)
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Algebra.Com's Answer #831014 by math_tutor2020(3817)\"\" \"About 
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\n" ); document.write( "Choices A and C are immediately ruled out because their domain is \"set of all real numbers\". \r
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\n" ); document.write( "\n" ); document.write( "The answer is one of the inverse trig functions either arcsine or arccosine.\r
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\n" ); document.write( "\n" ); document.write( "Refer to this page
\n" ); document.write( "https://www.alamo.edu/contentassets/35e1aad11a064ee2ae161ba2ae3b2559/trigonometric/math2412-inverse-trig-functions.pdf
\n" ); document.write( "To see how the y = sin(x) function has its domain restricted to the interval [-pi/2, pi/2] so that it becomes one-to-one. This allows the inverse to be possible. \r
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\n" ); document.write( "\n" ); document.write( "On the domain [-pi/2, pi/2] the corresponding range is [-1, 1]
\n" ); document.write( "When computing the inverse, the domain and range swap.
\n" ); document.write( "Therefore, the domain of arcsine is [-1,1] and its range is [-pi/2, pi/2]
\n" ); document.write( "This rules out choice B.\r
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\n" ); document.write( "\n" ); document.write( "You should find that y = cos(x) should have a domain restriction of [0, pi] so that we have a one-to-one portion.
\n" ); document.write( "This covers a range of [-1,1]
\n" ); document.write( "The domain and range swap leading arccos to have a domain of [-1,1] and range of [0,pi]
\n" ); document.write( "In short, this shows why choice D is the answer.\r
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\n" ); document.write( "\n" ); document.write( "Side note: I don't know why your teacher has excluded the endpoints. The endpoints should be included.
\n" ); document.write( "Something like f(x) = 0 is possible for f(x) = arccos(x). It occurs when x = 1.\r
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\n" ); document.write( "\n" ); document.write( "Answer: Choice D. f(x) = arccos(x)
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