Question

In triangle ABC , M is the mid- piont of BC . calculate cosB in triangle ABC. Hence calculate AM​

Answer 1

Answer:

In △ABC, M is mid point of AB and N is mid point of AC

D is any point of BC

Now, Join AD and MN such that they met at O

In △ABC

M is mid point of AB and N is mid point point of AC

Hence, MN∥BC and MN=

2

1

BC

Now, In △ABD

MO∥BC and M is mid point of AB

Thus, O is mid point of AD

Hence, MN bisects AD