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In A B C ,\ \ /A=60o . Prove that B C...

In ` A B C ,\ \ /_A=60o` . Prove that `B C^2=A B^2+A C^2-A B.A C .

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RD SHARMA-TRIANGLES-All Questions
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  2. There is a staircase as shown in Fig. 4.232, connecting points A an...

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  3. In A B C ,\ \ /A=60o . Prove that B C^2=A B^2+A C^2-A B.A C .

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  4. In A B C , /C is an obtuse angle. A D|B C and A B^2=A C^2+3\ B C^2...

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  5. A point D is on the side B C of an equilateral triangle A B C su...

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  6. In A B C , if B D|A C and B C^2=2\ A C C D , then prove that A B=...

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  7. In a quadrilateral A B C D , given that /A+/D=90o . Prove tha...

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  8. In A B C , given that A B=A C and B D|A C . Prove that B C^2=2\...

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  10. In A B C , A D is a median. Prove that A B^2+A C^2=2\ A D^2+2\ D C...

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  13. In a quadrilateral A B C D ,\ \ /B=90o . If A D^2=A B^2+B C^2+C D^2...

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  17. In the adjoining figure, find A C . (FIGURE)

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  18. In the adjoining figure, if A D is the bisector of /A , what is ...

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  19. State AAA similarity criterion.

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  20. State S S S similarity criterion.

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