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You can put this solution on YOUR website!
Solve the equations
\n" ); document.write( "I. cosxsinx-sinx=0
\n" ); document.write( "II. Cos3x+cos2x+cosx=0
\n" ); document.write( "III. 2cosx-3tanx
\n" ); document.write( "***
\n" ); document.write( "For interval [0,360˚]
\n" ); document.write( "cosxsinx-sinx=0
\n" ); document.write( "sinx(cosx-1)=0
\n" ); document.write( "sinx=0
\n" ); document.write( "x=0
\n" ); document.write( "or
\n" ); document.write( "cosx-1=0
\n" ); document.write( "cosx=1
\n" ); document.write( "x=0, 270˚
\n" ); document.write( "..\r
\n" ); document.write( "\n" ); document.write( "Cos3x+cos2x+cosx=0
\n" ); document.write( "cos3x=4cos^3-3cosx(found this in my pre-calc textbook)
\n" ); document.write( "cos2x=2cos^2x-1
\n" ); document.write( "4cos^3-3cosx+2cos^2x-1+cosx=0
\n" ); document.write( "4cos^3+2cos^2x-2cosx-1=0
\n" ); document.write( "(4cos^2x-2)(2cosx+1)=0 (figured this out using a graphing program on my computer)
\n" ); document.write( "4cos^2x-2=0
\n" ); document.write( "cos^2x=2/4=1/2
\n" ); document.write( "cosx=±√(1/2)
\n" ); document.write( "cosx=±√2/2
\n" ); document.write( "x=45˚, 315˚
\n" ); document.write( "or
\n" ); document.write( "2cosx+1=0
\n" ); document.write( "cosx=-1/2
\n" ); document.write( "x=300˚
\n" ); document.write( "..
\n" ); document.write( "2cosx-3tanx=0
\n" ); document.write( "
\n" ); document.write( "2cos^2(x)-3sin(x)=0
\n" ); document.write( "2(1-sin^2(x)-3sin(x)=0
\n" ); document.write( "2-2sin^2(x)-3sin(x)=0
\n" ); document.write( "2sin^2(x)+3sin(x)-2=0
\n" ); document.write( "(2sin(x)-1)(sin(x)+2)=0
\n" ); document.write( "2sin(x)-1=0
\n" ); document.write( "sin(x)=1/2
\n" ); document.write( "x=30˚
\n" ); document.write( "or
\n" ); document.write( "sin(x)+2=0
\n" ); document.write( "sin(x)=2 (reject,(-1 ≤ sinx ≤ 1))\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "