Degree
Degree
The word “degree” has several distinct meanings in science and mathematics. First, in physics, it refers to a unit of temperature. Common units of temperature are degrees Celsius (°C) and degrees Fahrenheit (°F). Absolute temperature is measured in Kelvins (not “degrees Kelvin”).
Second, in geometry, a degree is a unit of angle. A right angle is 90 degrees, the interior angles of a triangle always add to 180 degrees, and so on. Alternative units of angle are grads and radians.
Third, in algebra, “degree” refers to a property of polynomials. The degree of a polynomial in one variable (a monomial), such as 5x3, is the exponent, 3, of the variable. The degree of a monomial involving more than one variable, such as 3x2y, is the sum of the exponents; in this case, 2 + 1 = 3. The degree of a polynomial with more than one term is the highest degree among its monomial terms. Thus the degree of 5 x2y + 7 x3y2z2 + 8x4y is 3 + 2 + 2 = 7.
The degree of a polynomial equation is the highest degree among its terms. Thus the degree of the equation 5x3 –3x2 = x + 1 is 3.