document.write( "Question 1076558: Hi can someone help me with this problem please? THANK YOU! \r
\n" ); document.write( "\n" ); document.write( "Simplify the expression cos^-1[sin(-pi/6)] \n" ); document.write( "
Algebra.Com's Answer #691213 by Edwin McCravy(20054)\"\" \"About 
You can put this solution on YOUR website!
\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "The other tutor is right that \"matrix%281%2C3%2Csin%28-pi%2F6%29%2C%22%22=%22%22%2C-1%2F2%29\"\r\n" );
document.write( "\r\n" );
document.write( "But the rest is wrong because\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "Since he gave two answers, even though they are wrong, the\r\n" );
document.write( "fact that he gave two answers instead of one shows that he\r\n" );
document.write( "has forgotten that inverse trig functions are indeed \r\n" );
document.write( "functions.  Functions cannot have two output values for the \r\n" );
document.write( "same input value.  The range of the inverse cosine function \r\n" );
document.write( "is [0,p) \r\n" );
document.write( "\r\n" );
document.write( "So \"2pi%2F3\" is the only value.\r\n" );
document.write( "\r\n" );
document.write( "Edwin
\n" ); document.write( "
\n" );