मूलबिंदु से बिंदुओं `A(cos theta , sin theta ) ` एवं `B(cos phi ,sin phi ) ` को मिलाने वाली रेखा की लम्बवत दुरी ज्ञात कीजिए|

Explanation

दिया है:
` " "A =A (cos theta , sin theta ),B= B (cos phi, sin phi) `
`therefore ` AB का समीकरण
` " " (y-sin theta )/( x-cos theta ) =(sin phi -sin theta )/( cos phi -cos theta ) `
` " "= (2cos ((theta +phi )/(2) ) sin ((theta -phi )/(2)))/(2sin ((theta +phi )/(2))sin ((theta -phi )/(2)))=( (cos (theta +phi )/( 2)))/(-sin ((theta +phi )/(2)))`
` rArr " "xcos ((phi +theta)/(2))+ysin ((phi +theta )/(2))-{cos theta cos ((phi +theta )/(2))+sin theta *sin ((phi +theta )/(2))} =0`
`rArr" "xcos ((phi +theta )/( 2) ) +ysin ((phi +theta )/(2))-cos ((phi -theta )/(2))=0 " "...(i)`
यदि मूलबिंदु से समीकरण (i ) की लम्बवत दुरी d है, तब
` " "d= |0* cos ((phi+ theta )/(2))+0*sin ((phi +theta )/(2))-cos ((phi -theta )/(2))|/sqrt(cos ^(2) ((phi + theta)/(2))+sin ^(2) ((phi -theta )/(2)))=| cos ((phi -theta)/(2))| `
` " "` जो अभीष्ट दुरी है|