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Plz help me :(

Prove for any value of y the value of expression y^4−(y^2−9)(y^2+9) is divisible by 9.

User Gtournie
by
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2 Answers

3 votes

Answer:

Its 9*9

Explanation:

The equation equals 81 and 9*9=81.

Have a great day! :)

User Maulana Prambadi
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1 vote

PROOF:


y^4-(y^2-9)(y^2+9)\\=y^4 -(y^4-81)\\=y^4-y^4+81\\=81

And 81 is ALWAYS divisible by 9

User The DIMM Reaper
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4.9k points