document.write( "Question 1005892: I need help, I don't understand how to do this..\r
\n" ); document.write( "\n" ); document.write( "Find all solutions to the equation.\r
\n" ); document.write( "\n" ); document.write( "7 sin2x - 14 sin x + 2 = -5 \n" ); document.write( "

Algebra.Com's Answer #622023 by Fombitz(32388) $\"\"$ $\"About$

You can put this solution on YOUR website!
It's a quadratic equation in disguise.
\n" ); document.write( "Let $\"u=sin%28x%29\"$ , then,
\n" ); document.write( " $\"7u%5E2-14u%2B7=0\"$
\n" ); document.write( " $\"u%5E2-2u%2B1=0\"$
\n" ); document.write( "Now solve the quadratic in $\"u\"$ and back substitute to get the solution in $\"x\"$ .
\n" ); document.write( "Repost if you get stuck.\r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

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