A two colunm proof is a

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Step-by-step explanation:

A mathematical proof may be written using a paragraph, two-columns, or using a flow chart. The two-column proof is the method we use to present a logical argument using a table with two columns. Important information is usually given to help begin a proof and is usually the starting point of all proofs.

-1/2 +2

step-by-step explanation:

1. a^4+8a^3+24a^2+32a+16

2.y^8+8y^7+28y^6+56y^5+70y^4+56y^3+28y^2+8y+1

3.x^6-3x^4y^2+3x^2y^4-y^6