Answer:
![\displaystyle \frac{(a - b)^(2) - {c}^(2) }{{a}^(2) - {(b+ c)}^(2) } + \frac{(b - c)^(2) - {a}^(2) }{{b}^(2) - {(c+ a)}^(2) } + \frac{(c - a)^(2) - {b}^(2) }{{c}^(2) - {(a+ b)}^(2) }=1](https://img.qammunity.org/2022/formulas/mathematics/high-school/uin1e8yq34rydjn6cu3jcia72udn89l3kc.png)
Explanation:
Algebra Simplifying
We are given the expression:
![\displaystyle T=\frac{(a - b)^(2) - {c}^(2) }{{a}^(2) - {(b+ c)}^(2) } + \frac{(b - c)^(2) - {a}^(2) }{{b}^(2) - {(c+ a)}^(2) } + \frac{(c - a)^(2) - {b}^(2) }{{c}^(2) - {(a+ b)}^(2) }](https://img.qammunity.org/2022/formulas/mathematics/high-school/dyz2e83fqckvr34jk4jr62ug5opd0gcwww.png)
We need to repeatedly use the following identity:
![(a^2-b^2)=(a-b)(a+b)](https://img.qammunity.org/2022/formulas/mathematics/high-school/ajwlhjys428vowlzk5bvoadmdi7spye151.png)
For example, the first numerator has a difference of squares thus we factor as:
![(a - b)^(2) - {c}^(2) =(a-b-c)(a-b+c)](https://img.qammunity.org/2022/formulas/mathematics/high-school/ugx7zgon2zcdh70fqxohk0pjmy48vl1ab0.png)
The first denominator can be factored also:
![{a}^(2) - {(b+ c)}^(2) = (a-b-c)(a+b+c)](https://img.qammunity.org/2022/formulas/mathematics/high-school/jbp64dcb99dt021bhfjxedz0wz473puby9.png)
Applying the same procedure to all the expressions:
![\displaystyle T=((a - b- c)(a-b+c) )/(a-b-c)(a+b+c) ) + ((b - c - a)(b-c+a) )/((b-c-a)(b+c+a) ) + ((c - a-b)(c-a+b) )/((c-a-b)(c+a+b))](https://img.qammunity.org/2022/formulas/mathematics/high-school/cbfua3gi09tr065rdmcyqfihra04nw5hf1.png)
Simplifying all the fractions:
![\displaystyle T=(a - b- c)/(a+b+c) + (b-c+a)/(b+c+a ) + (c-a+b )/(c+a+b)](https://img.qammunity.org/2022/formulas/mathematics/high-school/xr5x6zysxz7a5ek1p6ej8lbq7vf4kuty4s.png)
Since all the denominators are equal:
![\displaystyle T=(a - b+ c+b-c+a+c-a+b)/(a+b+c)](https://img.qammunity.org/2022/formulas/mathematics/high-school/7xb844ck2kfjvdrzm2013d3xix9ephkoxg.png)
Simplifying:
![\displaystyle T=(a +c+b)/(a+b+c)](https://img.qammunity.org/2022/formulas/mathematics/high-school/yh6ufyrpgmem1d5tv8681nvbignn84rc2x.png)
Simplifying again:
T = 1
Thus:
![\boxed{\displaystyle \frac{(a - b)^(2) - {c}^(2) }{{a}^(2) - {(b+ c)}^(2) } + \frac{(b - c)^(2) - {a}^(2) }{{b}^(2) - {(c+ a)}^(2) } + \frac{(c - a)^(2) - {b}^(2) }{{c}^(2) - {(a+ b)}^(2) }=1}](https://img.qammunity.org/2022/formulas/mathematics/high-school/eva2rb3bmd8bm60digoyx18mh35tasecz7.png)