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Algebraic proof challenge question

Prove that “2x^3 plus 3x^2 plus x” is always divisible by 6
(edited 6 years ago)
Original post by moody_badger
Prove that 2x^3 3x^2 x is always divisible by 6


Combine them into a single power of x with a 6 next to it. This means that the result is divisible by 6
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yusyus
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Original post by moody_badger
Prove that “2x^3 3x^2 x” is always divisible by 6


you could also try proof by induction if you know what that is
Original post by moody_badger
Prove that “2x^3 plus 3x^2 plus x” is always divisible by 6


2x3+3x2+x2x^3+3x^2+x

You can either:

a) Use induction as already suggested, or

b) Factorise, and show it's divisible by 2, and divisible by 3, hence it's divisible by 6.

Edit: On further reflection, you can just work with the original form directly, and show it's divisible by 2 and by 3.
(edited 6 years ago)

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