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Official solution
1. Let a=x−1x2, b=x−1, and c=x2x−1. Notice that abc=1 because: abc=(x−1x2)(x−1)(x2x−1)=(x−1)⋅x2x2⋅x−1⋅x−1=(x−1)⋅x2x2⋅(x−1)=1
2. Given the equation: a+b+c=a1+b1+c1 Substitute a, b, and c: x−1x2+x−1+x2x−1=x2x−1+x−11+x−1x2
3. Using the fact that abc=1, we can rewrite the equation as: a+b+c=a1+b1+c1 This implies: a+b+c=a1+b1+c1
4. We can rewrite the equation as: a+b+c=a1+b1+c1 Since abc=1, we have: a+b+ab1=a1+b1+ab
5. Rearrange the terms: a+b+ab1=a1+b1+ab This can be factored as: (a−1)(b−1)(ab−1)=0
6. Solving each factor: - If a=1: x−1x2=1⟹x2=x−1⟹x2−x+1=0 The discriminant of this quadratic equation is: Δ=(−1)2−4⋅1⋅1=1−4=−3 Since the discriminant is negative, there are no real solutions for x.
- If b=1: x−1=1⟹x−1=1⟹x=2
- If ab=1: x−1x2⋅x−1=1⟹x−1x2x−1=1⟹x2x−1=x−1 Let y=x−1, then y2=x−1 and the equation becomes: x2y=y2⟹x2=y⟹x2=x−1 Squaring both sides: x4=x−1⟹x4−x+1=0 This is a quartic equation and solving it analytically is complex. However, we already have x=2 as a solution from the previous factor.
7. Verify x=2: a=2−122=4,b=2−1=1,c=222−1=41 a+b+c=4+1+41=5.25 a1+b1+c1=41+1+4=5.25 Both sides are equal, confirming x=2 is a solution.
The final answer is x=2
Source: NuminaMath-1.5,
licensed Apache-2.0.
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