Упростите выражение a^3-(a+1)^3+3a^2

Question

Упростите выражение
a^3-(a+1)^3+3a^2

Comments

a^3-(a+1)^3+3a^2=a^3-a^3-1^3+3a^2=3a^2-1

Answer 1

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a^3-(a^3+3a^2+3a+1)+3a^2=a^3-a^3-3a^2-3a-1+3a^2=3a-1
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