First I will present the polynomial itself: it is
5x^3 - 22x^2 - 3x - 53.
Let's show that when this poly. is divided by (x-5), the quotient is 5x^2 + 3x + 12 and the remainder is 7. Use synthetic division here. Let the divisor be 5 (this comes from the factor (x-5). Then:
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5 / 5 -22 -3 -53
25 15 60
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5 3 12 7 where 5 3 12 are the coeff. of the quotient and 7
is the remainder.
Now work backwards. Multiply (x-5) and (5x^2 + 3x + 12) together. We get
5x^3 + 3x^2 + 12 x - 25x^2 - 15x - 60, or
5x^3 - 22x^2 - 3x - 60. Now add the remainder (7) to -60; the result will be -53.
So the poly in question is 5x^3 - 22x^2 - 3x - 53.
