Degree of a Constant
Date: 12/02/2002 at 14:10:12 From: Joy Sapienza Subject: Degree of a constant Dear Dr. Math, Why is the degree of a constant zero? We have just finished studying that any number to the zero power is one. It makes sense that the degree of a monomial like 2x is one, but it doesn't make sense to me that in a constant like 5, the degree is zero. Please help. Thank you, Joy
Date: 12/02/2002 at 14:41:35 From: Doctor Ian Subject: Re: Degree of a constant Hi Joy, It looks like you mostly figured it out yourself. Each term in a polynomial is the product of a constant (which may be 1 or 0) and a variable raised to an exponent, e.g., 3x^4 + 0x^3 + 1x^2 + 5x^1 + 7x^0 For convenience, we leave out terms where the coefficient is zero, 3x^4 + 1x^2 + 5x^1 + 7x^0 and we leave multiplication by 1 implied, 3x^4 + x^2 + 5x^1 + 7x^0 We abbreviate x^1 as just x, 3x^4 + x^2 + 5x + 7x^0 and we simplify x^0 to 1... which is left implied (see above): 3x^4 + x^2 + 5x + 7 So it's convenient to write a polynomial this way, but it's much cleaner for the definition to require no special cases: n --- \ i p(x) = / a x --- i i=0 When n=0, we get 0 a x = a 0 0 When you look at it this way, a constant is just a very short polynomial. This is nice, because you can just have one set of rules for dealing with polynomials of any degree, and constants are covered by it. Does this make sense? - Doctor Ian, The Math Forum http://mathforum.org/dr.math/
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