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Find a monic quadratic polynomial f(x) such that the remainder when f(x) is divide by x-1 is 2 and the remainder when f(x) is divided by x-3 is 4. Give your answer in the form.

User Nsemeniuk
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To find a monic quadratic polynomial with specific remainders, we utilized the Remainder Theorem and solved for constants to obtain f(x) = x² - x - 2.

To find a monic quadratic polynomial f(x) with specific remainders when divided by (x-1) and (x-3), we can use the Remainder Theorem.

We know the remainders when the polynomial is divided by these linear factors.

Therefore, we can express f(x) as:

f(x) = (x - 1)(x - 3)Q(x) + ax + b,

where Q(x) is a polynomial and a, b are constants that determine our remainders.

Since f(x) is monic, the coefficient of x² in Q(x) is 1.

We're given that f(1) = 2 and f(3) = 4, which gives us two equations:

f(1) = (1 - 1)(1 - 3)Q(1) + a*1 + b = 2

f(3) = (3 - 1)(3 - 3)Q(3) + a*3 + b = 4

Simplifying, we get:

a + b = 2

3a + b = 4

Subtracting the first equation from the second, we find 2a = 2, so a = 1. Substituting a into the first equation, b must be 1 as well.

Thus, our polynomial is f(x) = (x - 1)(x - 3) + x + 1 = x² - 3x + x - 3 + x + 1 = x² - x - 2.

User Leypascua
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