document.write( "Question 1196692: what happens to sinθ as θ approaches 0 radians? Why? \n" ); document.write( "
Algebra.Com's Answer #829633 by MathLover1(20855)\"\" \"About 
You can put this solution on YOUR website!
The way most people first encounter sine is as a ratio of two sides of a triangle.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "graph\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "In this case:\r
\n" ); document.write( "\n" ); document.write( "1. the sloping lines are all radii of the circle and represent the hypotenuse
\n" ); document.write( "2. the vertical lines are the ‘opposite’ side of the various triangles\r
\n" ); document.write( "\n" ); document.write( "As you can clearly see, as the angle reduces from \r
\n" ); document.write( "\n" ); document.write( " \"85\"° → \"60\"° → \"45\"° → \"30\"° →\"15\"° →\"10\"° →\"5\"° →\"1\"° \r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "the height of the vertical line (’opposite’) shrinks while the sloping line (‘hypotenuse’) remains constant \r
\n" ); document.write( "\n" ); document.write( " So the fraction opposite hypotenuse will, does and indeed \"must+\"\"reduce\" to \"0\" as \"theta\" reduces to \"0\" .\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "The more modern way to define sine is with an infinite series:\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"sin%28x%29=x-x%5E3%2F3%21%2Bx%5E5%2F5%21-x%2A7%2F7%21\"+….... \r
\n" ); document.write( "\n" ); document.write( "\"sin%28x%29=x%281-x%5E2%2F3%21%2Bx%5E4%2F5%21-x%5E6%2F7%21%2Bx%5E8%2F9%21%29\".... \r
\n" ); document.write( "\n" ); document.write( "But you can see how that also goes to zero as \"theta\" goes to zero!\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "
\n" ); document.write( "
\n" );