3) VT = $\frac{-(b-c)^2}{(a-b)(b-c)(c-a)}+\frac{-(c-a)^2}{(a-b)(b-c)(c-a)}+\frac{-(a-b)^2}{(a-b)(b-c)(c-a)}$ = $-\frac{(a-b)^2+(b-c)^2+(c-a)^2}{(a-b)(b-c)(c-a)}=\frac{2ab+2bc+2ca-2a^2-2b^2-2c^2}{(a-b)(b-c)(c-a)}$ VP = $\frac{2(b-c)(c-a)+2(c-a)(a-b)+2(a-b)(b-c)}{(a-b)(b-c)(c-a)}$ = $\frac{(2bc-2ab-2c^2+2ca)+(2ca-2bc-2a^2+2ab)+(2ab-2ca-2b^2+2bc)}{(a-b)(b-c)(c-a)}$ = VT
3) VT = $\frac{(
a-c)
-(a-b)}{(a-b)(
a-c)}+\frac{(
b-a)
-(b
-c)
}{(b-c)(
b-a)}+\frac{(
c-b)
-(
c-
a)
}{(c
-a)(c-
b)}$ = $\frac{
1}{a-b}
-\frac{
1}{a-c}
+\frac{
1}{b-c}
-\frac{
1}{b-a
}+
\frac
{1}{c-a
}-
\frac
{1}{c-
b}$ = V
P