Có S=abc/4R=rp =>4Rr=abc/p
r^2.p=S^2/p=(p-a)(p-b)(p-c) (hê rông)
đăng thứccần c/m
<=>p(ab+bc+ca)=p^3+(p-a)(p-b)(p-c)+abc
<=>dpcm
winter_29's Content
There have been 1 items by winter_29 (Search limited from 21-05-2020)
There have been 1 items by winter_29 (Search limited from 21-05-2020)