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AD is a median of the triangle ABC. Is it true that AB + BC + CA > 2AD? Give reason for your answer.

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प्रश्न

AD is a median of the triangle ABC. Is it true that AB + BC + CA > 2AD? Give reason for your answer.

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उत्तर

In triangle ABD,

AB + BD > AD  ...(i)

AC + CD > AD  ...(ii) [Sum of the length of any two sides of a triangle must be greater must be greater that the third side]

Adding (i) and (ii), we get

AB + BD + CD + AC > 2AD

AB + BC + CA > 2AD   ...[BD = CD as AD is median of triangle ABC]

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अध्याय 7: Triangles - Exercise 7.2 [पृष्ठ ६५]

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एनसीईआरटी एक्झांप्लर Mathematics Exemplar [English] Class 9
अध्याय 7 Triangles
Exercise 7.2 | Q 9. | पृष्ठ ६५

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