The Polynomial Remainder Theorem states that the remainder of the division of a polynomial f(x) by a linear polynomial x−r is equal to f(r). In particular, x−r divides f(x)⟺f(r)=0
But what if the divisor is not linear and of a degree higher than one?
Consider this question:
Let P(x) be any polynomial. When it is divided by (x−13) and (x−17), then the remainders are 15 and 35 respectively. The remainder, when P(x) is divided by (x−13)(x−17), is
How I approached it:
P(13)=15
P(17)=35
But how do I figure out the remainder if the degree of the divisor is greater than one?
Answer
Alternative hint:
P(x)=g(x)(x−13)(x−17)+ax+b
for some a and b . Your recovered values of P(13)=15 and P(17)=35 give you two linear equations to solve for a and b .
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