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How many integer values of r satisfy the equation ³⁹C_(3r-1) - ³⁹C_(r²) = ³⁹C_(r²-1) - ³⁹C_(3r)?
- 1
- 2
- 3
- 4
Correct answer: 2
Solution
The equation involves combinations that can be simplified and analyzed for integer solutions. By examining the properties of binomial coefficients and their relationships, we find that there are exactly two integer values of r that satisfy the equation.
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