f(x)=(x+5)²(x-1)
=(x-1)(x²+10x+25)
=x²(x-1)+10x(x-1)+25(x-1)
=x³-x²+10x²-10x+25x-25
=x³+9x²+15x-25
( x + 5 ) 2 ( x − 1 ) = ( x 2 + 10 x + 25 ) ( x − 1 ) = x 3 − x 2 + 10 x 2 − 10 x + 25 x − 25 = x 3 + 9 x 2 + 15 x − 25
The polynomial function with the given zeroes is f ( x ) = x 3 + 9 x 2 + 15 x − 25 . This was achieved by first creating a factored form of the polynomial based on the zeroes and then expanding it to standard form. The zeroes are x = -5 (with multiplicity 2) and x = 1.
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