document.write( "Question 615276: I need to find solutions in the interval (0,2pi)cos^2x=1-sinx \n" ); document.write( "
Algebra.Com's Answer #387088 by jsmallt9(3758)\"\" \"About 
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\"cos%5E2%28x%29=1-sin%28x%29\"
\n" ); document.write( "First use \"cos%5E2%28x%29+=+1+-+sin%5E2%28x%29\" to change the equation into an \"all-sin\" equation:
\n" ); document.write( "\"1+-+sin%5E2%28x%29=1-sin%28x%29\"

\n" ); document.write( "Next we solve for sin(x). This equation is quadratic in terms of sin(x) so we want one side to be zero. Subtracting 1 and adding \"sin%5E2%28x%29\" to each side we get:
\n" ); document.write( "\"0+=+sin%5E2%28x%29+-+sin%28x%29\"
\n" ); document.write( "Factor. The GCF is sin(x):
\n" ); document.write( "0 = sin(x)(sin(x) - 1)
\n" ); document.write( "Use the Zero Product Property:
\n" ); document.write( "sin(x) = 0 or sin(x) - 1 = 0
\n" ); document.write( "Solving the second equation we get:
\n" ); document.write( "sin(x) = 0 or sin(x) = 1

\n" ); document.write( "Now that we have solved for sin(x), we can solve for x. Sin values of 0 and 1 are special angle values. So we do not need a calculator. From the special angles we know that...
\n" ); document.write( "For sin(x) = 0:
\n" ); document.write( "\"x+=+0+%2B+2%2Api%2An\"
\n" ); document.write( "or
\n" ); document.write( "\"x+=+pi+%2B+2%2Api%2An\"
\n" ); document.write( "For sin(x) = 1:
\n" ); document.write( "\"x+=+pi%2F2+%2B+2%2Api%2An\"

\n" ); document.write( "From these three equations we can find all the x's that are in the specified interval.
\n" ); document.write( "From \"x+=+0+%2B+2%2Api%2An\"...
\n" ); document.write( "We get no solutions. (Did you post the interval correctly? I ask because often there is a bracket, not a parenthesis, on one or maybe both ends of the interval. A bracket at one of end of an interval means \"including the number at that end\". A parenthesis means \"not including....\" Since you posted parentheses at both ends, 0 and \"2pi\" are excluded. If either one of these is supposed to be included, then this equation says they would be a solution in the interval.)

\n" ); document.write( "From \"x+=+pi+%2B+2%2Api%2An\"...
\n" ); document.write( "we get \"x+=+pi\" as the only solution within the specified interval.

\n" ); document.write( "From \"x+=+pi%2F2+%2B+2%2Api%2An\"...
\n" ); document.write( "we get \"x+=+pi%2F2\" as the only solution within the specified interval.
\n" ); document.write( "
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