Hi please help me solve this problem
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Answer:
( a + b ) ( b + c ) ( c + a )
Step-by-step explanation:
There are two things to make use of here.
First, in both the numerator and the denominator, the sum of the terms that get cubed is zero. That is,
(a²-b²) + (b²-c²) + (c²-a²) = 0 and (a-b) + (b-c) + (c-a) = 0.
Second, when x+y+z=0, we have x³+y³+z³ = 3xyz. To see this, just consider the expansion
(x+y+z)³ = (x³+y³+z³) + 3(x+y+z)(xy+yz+zx) - 3xyz
and substitute x+y+z=0.
Putting these two facts together, the numerator is equal to
3(a²-b²)(b²-c²)(c²-a²) = 3(a-b)(a+b)(b-c)(b+c)(c-a)(c+a)
and the denominator is equal to
3(a-b)(b-c)(c-a),
so the whole expression simplifies to
(a+b)(b+c)(c+a).
Hope that helps!
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