document.write( "Question 1182204: Which of the following values of x is a solution to the equation sinx + cos x=1?\r
\n" ); document.write( "\n" ); document.write( "x=45°
\n" ); document.write( "x=90°
\n" ); document.write( "x=135°
\n" ); document.write( "x=180° \n" ); document.write( "

Algebra.Com's Answer #812238 by ikleyn(52777) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "This problem was posted to the forum couple of days ago, and I gave its full solution under this link\r
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\n" ); document.write( "\n" ); document.write( "https://www.algebra.com/algebra/homework/Functions/Functions.faq.question.1182143.html\r
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\n" ); document.write( "\n" ); document.write( "https://www.algebra.com/algebra/homework/Functions/Functions.faq.question.1182143.html\r
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\n" ); document.write( "\n" ); document.write( " For your convenience, I copy-paste that solution here again\r
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document.write( "Starting from\r\n" );
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document.write( "    sin(x) + cos(x) = 1,      (1)\r\n" );
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document.write( "square both sides\r\n" );
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document.write( "     = 1.      (2)\r\n" );
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document.write( "Take into account that   +  == 1.\r\n" );
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document.write( "You will get then from  (2)\r\n" );
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document.write( "    2*sin(x)*cos(x) = 0,\r\n" );
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document.write( "or\r\n" );
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document.write( "      sin(x(*cos(x) = 0.\r\n" );
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document.write( "So, equation (1) implies\r\n" );
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document.write( "    sin(x) = 0  or  cos(x) = 0.\r\n" );
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document.write( "It gives  x =   or  x = ,   where k is any integer number.\r\n" );
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document.write( "Checking these potential solutions,  we get the final answers  x = ,  or  x = ,  where n is any integer number.\r\n" );
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document.write( "Of the given four optional choices,  only  x= 90°  is the solutions to the given equation.\r\n" );
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