document.write( "Question 1042126: CotA =4/3 and (a+b)=90degree find the value of tanB = ?
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Algebra.Com's Answer #657099 by ikleyn(52908) $\"\"$ $\"About$

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\n" ); document.write( "Cot(A) = 4/3 and (A+B) = 90 degree. Find the value of tan(B) = ?
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document.write( "Since A + B = 90°, you have B = 90° - A.\r\n" );
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document.write( "Now, tan(B) = tan(90°-A) = cot(A).\r\n" );
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document.write( "It is a standard trigonometry identity (see, for example, this site). \r\n" );
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document.write( "Therefore, tan(B) = cot(A) = .\r\n" );
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\n" ); document.write( "\n" ); document.write( "The solution of the other tutor contains very serious error, so disregard it.\r
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\n" ); document.write( "\n" ); document.write( "In particular, he writes\r
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\n" ); document.write( "\n" ); document.write( " \"If (a+b) = 90 then tan(a+b)= tan 90
\n" ); document.write( " We know that tan 90 = 0 then tan(a+b)= 0\"\r
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\n" ); document.write( "\n" ); document.write( "which is totally wrong. Everybody knows that tan(90°) is not defined (\"is infinity\").\r
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\n" ); document.write( "\n" ); document.write( "This is why I wrote this post for you.\r
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