Question 883445
Verify the identity: {{{(1-cos(2x))/(2sin(x)+sin(2x))=tan(x/2)}}}
start with left side
{{{(1-cos(2x))/(2sin(x)+sin(2x))}}}
{{{(1-cos^2(x)+sin^2(x))/(2sin(x)+2sin(x)cos(x))}}}
{{{(sin^2(x)+sin^2(x))/(2sin(x)(1+cos(x)))}}}
{{{(2sin^2(x))/(2sin(x)(1+cos(x)))=sin(x)/(1+cos(x))=tan(x/2)}}}
verified: left side=right side