document.write( "Question 1203820: Find all exact solutions on the interval 0 ≤ x < 2𝜋. (Enter your answers as a comma-separated list.)
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Algebra.Com's Answer #839658 by ikleyn(52873) $\"\"$ $\"About$

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\n" ); document.write( "Find all exact solutions on the interval 0 ≤ x < 2𝜋. (Enter your answers as a comma-separated list.)
\n" ); document.write( "cot(x) + 5 = 6
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document.write( "    cot(x)  +  5  =  6  implies, step by step\r\n" );
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document.write( "    cot(x) = 6 - 5\r\n" );
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document.write( "    cot(x) = 1\r\n" );
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document.write( "    x =   or  x = .\r\n" );
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document.write( "ANSWER.  There are two solutions in the given interval:  x =   or  x = .\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved.\r
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\n" ); document.write( "\n" ); document.write( "Regarding the solution by @Theo to this problem, notice that the part of his reasoning and calculations
\n" ); document.write( "below his plot, where he considers cotan(7) and arctan(1/7), is fully irrelevant to the problem
\n" ); document.write( "and is placed there by him for unknown reasons (by mistake ?).\r
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\n" ); document.write( "\n" ); document.write( "Regarding his other notice that solving equation cot(x) = 1 requires to convert cotangent to equivalent tangent function,
\n" ); document.write( "I would be more careful with such statements.\r
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\n" ); document.write( "\n" ); document.write( "This equation, cot(x) = 1 requires only knowledge of basic notions of Trigonometry
\n" ); document.write( "and knowledge of table values of basic trigonometric functions.\r
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\n" ); document.write( "\n" ); document.write( "In general, this idea by @Theo to use a calculator to solve equation cot(x) = 1
\n" ); document.write( "does not seem a productive to me. A student, who is literate in Trigonometry,
\n" ); document.write( "should/MUST solve such equation MENTALLY, and it is a right way to teach.\r
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\n" ); document.write( "\n" ); document.write( "If a student uses a calculator for such purposes, it clearly shows that this student
\n" ); document.write( "does not know the basics of Trigonometry. Such a student must re-learn
\n" ); document.write( "the basics of Trigonometry from scratch.\r
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\n" ); document.write( "\n" ); document.write( "So, my impression is that the whole @Theo's post is WRONG TEACHING.\r
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