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In a quadrilateral A B C D ,\ C O\ a n d...

In a quadrilateral `A B C D ,\ C O\ a n d\ D O` are the bisectors of `/_C\ a n d\ /_D` respectively. Prove that `/_C O D=1/2(/_A+/_B)dot`

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`Given=> CO and DO "are the bisectors of" /_C and /_D`
`therefore /_C =/_1+ /_4 and /_1=/_4->"(1)"`
`/_D=/_3 + /_5 and /_3=/_5->"(1)"`
`"To prove:" ∠COD=1/2(/_A+/_B)`
`=>"Proof":/_A+/_B+/_C+/_D=360^0 - ("angle sum property")`
`therefore 1/2/_A+1/2/_B+1/2/_C+1/2/_D=360/2`
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RD SHARMA-QUADRILATERALS-All Questions
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