document.write( "Question 634796: Hi, I've been stuck on this one for a considerable amount of time.
\n" ); document.write( "=> Show that the equation 4cos(2x)-3sin(x)csc(x)^3+6 = 0, can be expressed as
\n" ); document.write( "8y^4-10y^2+3=0 if sin(x) = y
\n" ); document.write( "Hence, solve the equation for x\r
\n" ); document.write( "\n" ); document.write( "Thankyou for your help \n" ); document.write( "

Algebra.Com's Answer #399921 by ewatrrr(24785) $\"\"$ $\"About$

You can put this solution on YOUR website!

 
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document.write( "Hi,
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document.write( "4cos(2x)-3sin(x)csc(x)^3+6 = 0
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document.write( "4cos(2x)-3/sin^2(x)+6 = 0
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document.write( "cos(2x)= 1-2sin^2x
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document.write( "4(1-2sin^2x) - (3/sin^2(x))+6 = 0  |Multiplying thru by sin^2x so as all denominators = 1
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document.write( " -8sin^4 + 4sin^2 - 3 + 6sin^2x = 0
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document.write( " 8sin^4 + 10sin^2 - 3  = 0
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document.write( "8y^4-10y^2+3=0    if sin(x) = y \n" );
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