since we're dealing with sum of cubes,
2^90 + 5^90 = (2^30 + 5^30)(2^60-10^30+5^60)
2^30 + 5^30 = (2^10 + 5^10)(2^20-10^10+5^20)
2^10 + 5^10 = 29*336781
Prove that 29|2⁹⁰ + 5⁹⁰.
I am not sure how to go about proving this divisiblity problem. Can anyone help me on how to go about the process to solve it? Thanks so much.
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1 answer