數學測驗唔識...

-終場ソ使者-

1)
You prove AE//OM
<ADO=<DAO
<DOM=<ADO
<MOB=<DAO
<DOM=<MOB

2.1)
Domain (for x) is -4<x<2
2.2)
To find max of A(x),
just consider the height of tri. PRQ (PR is its base)
since PR is a constant, A'(x) is directly prop. to its height   (A'(x) represents the area of tri. PRQ)
ie find the max height
therefore, A(x)=2A'(x)

-終場ソ使者-

in fact mid-pt thm may be a better for proving AE//OM !