document.write( "Question 958546: Of the infinitely many lines that are tangent to the curve of y = -sin x and pass through the origin, there is one that has the largest slope. Use Newton's method to find the slope of that line correct to six decimal places. \n" ); document.write( "
Algebra.Com's Answer #585936 by Fombitz(32388)\"\" \"About 
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\"graph%28300%2C300%2C-7%2C7%2C-2%2C2%2C-sin%28x%29%29\"
\n" ); document.write( "A line tangent to the curve \"y=-sin%28x%29\" at point has a slope of \"m=-cos%28x%29\".
\n" ); document.write( "Since it goes through point (\"x\",\"y\") and the origin then the slope also equals.
\n" ); document.write( "\"m=%28y-0%29%2F%28x-0%29=y%2Fx=-sin%28x%29%2Fx\"
\n" ); document.write( "So then,
\n" ); document.write( "\"-sin%28x%29%2Fx=-cos%28x%29\"
\n" ); document.write( "\"sin%28x%29-xcos%28x%29=0\"
\n" ); document.write( "So to find the root, let
\n" ); document.write( "\"f%28x%29=sin%28x%29-xcos%28x%29\"
\n" ); document.write( "Then,
\n" ); document.write( "\"df%2Fdx=xsin%28x%29\"
\n" ); document.write( "Now using Newton's method with a starting value of \"x=4\"
\n" ); document.write( ".
\n" ); document.write( "So then at \"x=4.493409\", the slope is equal to,
\n" ); document.write( "\"m=-cos%284.493409%29\"
\n" ); document.write( "\"highlight%28m=0.217234%29\"
\n" ); document.write( "\"graph%28300%2C300%2C-7%2C7%2C-2%2C2%2C-sin%28x%29%2C0.217234x%29\"
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