document.write( "Question 1198723: Given cot theta =-2 and csc theta < 0, find sin theta and sec theta \n" ); document.write( "
Algebra.Com's Answer #832552 by math_tutor2020(3817)\"\" \"About 
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\n" ); document.write( "In response to what the tutor @MathLover1 wrote: Cotangent is NOT negative in quadrant Q3.
\n" ); document.write( "Take note how sine and cosine are indeed negative here, so,
\n" ); document.write( "cot = cos/sin
\n" ); document.write( "the two negative items divide to a positive result.\r
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\n" ); document.write( "\n" ); document.write( "In short, cotangent is positive in Q3.\r
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\n" ); document.write( "\n" ); document.write( "Since cot(theta) = -2 is negative, this places theta in either Q2 or Q4.\r
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\n" ); document.write( "\n" ); document.write( "Then we're told csc(theta) < 0, which fully narrows things down to Q4 only.
\n" ); document.write( "270 < theta < 360 in degree mode
\n" ); document.write( "3pi/2 < theta < 2pi in radian mode
\n" ); document.write( "The actual theta value itself doesn't matter; however, this interval helps narrow things down a bit.\r
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\n" ); document.write( "\n" ); document.write( "Since cot(theta) = -2 = 2/(-1), we could have a triangle with adjacent side 2 and opposite side -1.
\n" ); document.write( "I'll make the opposite length \"negative\" so that we can keep the proper signs in mind. Of course a negative length isn't possible.
\n" ); document.write( "It's purely as a means to retain information.
\n" ); document.write( "I'm making the 1 negative so that it indicates we're below the x axis, i.e. the y coordinate is negative.\r
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\n" ); document.write( "\n" ); document.write( "Use the pythagorean theorem to find the hypotenuse is sqrt(5) units long.\r
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\n" ); document.write( "\n" ); document.write( "This is one way to draw the triangle in Q4
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\n" ); document.write( "We have:
\n" ); document.write( "opposite = -1
\n" ); document.write( "adjacent = 2
\n" ); document.write( "hypotenuse = sqrt(5)\r
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\n" ); document.write( "\n" ); document.write( "Then recall that
\n" ); document.write( "sin(theta) = opposite/hypotenuse
\n" ); document.write( "sec(theta) = hypotenuse/adjacent\r
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\n" ); document.write( "\n" ); document.write( "I'll let you finish up from here.
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