Find a polynomial function of degree 3 with real coefficients that has the given zeros of -3, -1 and 4 for which f(-2) = 24.
Solution:
Given, the roots of the polynomial function of degree 3 are -3, -1 and 4.
f(-2) = 24
So, f(x) = a(x - 4)(x + 3)(x + 1)
f(x) = a(x2 + 3x - 4x - 12) (x + 1)
= a(x2 - x - 12)(x + 1)
= a(x3 + x2 - x2 - x - 12x - 12)
f(x) = a(x3 - 13x - 12)
f(-2) = 24 = a(x3 - 13x - 12)
a(((-2)3 - 13(-2) - 12) = 24
a(-8 + 26 - 12) = 24
a(26 - 20) = 24
a(6) = 24
a = 24/6
a = 4
Therefore, polynomial function is 4(x - 4)(x + 3)(x + 1)
Find a polynomial function of degree 3 with real coefficients that has the given zeros of -3, -1 and 4 for which f(-2) = 24.
Summary:
A polynomial function of degree 3 with real coefficients that has the given zeros of -3, -1 and 4 for which f(-2) = 24 is 4(x - 4)(x + 3)(x + 1).
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