Which algebraic expression is a polynomial with a degree of 2 ?

A polynomial of degree 2 has only nonnegative whole-number exponents, and its greatest exponent is 2. In choice C, 6x² − 6x + 5 has exponents 2, 1, and 0, so it is a polynomial of degree 2. Choice A contains √x, which has exponent 1/2; choices B and D contain terms with degree 3.

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