
In the above figure, AD is a bisector angle A (angle BAC). How do I prove in a triangle ABC of any dimensions that,
- $AB > BD$
- $AC > CD$
Is it also possible to prove that,
- $AB > AD$
- $AC > AD$

In the above figure, AD is a bisector angle A (angle BAC). How do I prove in a triangle ABC of any dimensions that,
Is it also possible to prove that,
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I think the first two can be proven. Let $BC=a, AC=b, AB=c$
Now, using angle bisector theorem,$$\frac{CD}{BD}=\frac{b}{c}$$ $$BD=\frac{c}{b+c}.a$$$$CD=\frac{b}{b+c}.a$$ But $b+c>a$ $$\implies BD<c$$$$\implies CD<b$$
However as mentioned the comments, the next two parts do not always hold.