Q. A function s is defined as s(x)=(x−4)(x−5)2. A function h is defined as h(x)=(x−a)⋅s(x). For some constant a,(x−a)3 is a factor of h. What is s(a) ?
Given: Given:s(x)=(x−4)(x−5)2h(x)=(x−a)⋅s(x)We need to find s(a) given that (x−a)3 is a factor of h(x).
Factor of h(x): Since (x−a)3 is a factor of h(x), it means that (x−a) is a factor of s(x) because h(x)=(x−a)⋅s(x).
Calculate s(a): To find s(a), we need to substitute x with a in the expression for s(x):s(a)=(a−4)(a−5)2
Determine value of a: However, before we calculate s(a), we need to determine the value of a. Since (x−a)3 is a factor of h(x), and we know that h(x)=(x−a)⋅s(x), this implies that (x−a) must also be a factor of s(x) on its own.
Factor s(x): We can factor s(x) to see if (x−a) appears as a factor:s(x)=(x−4)(x−5)(x−5)
Determine a: For (x−a) to be a factor of s(x), a must be either 4 or 5 because those are the roots of s(x).
Calculate s(5): Since (x−a)3 is a factor of h(x), and we already have (x−a) as a factor of s(x), (x−a) must be repeated three times in total. This means that a must be 5 because (x−5) is already squared in s(x), and multiplying by (x−a) from h(x) would give us (x−a)32.Now that we have determined (x−a)3, we can calculate (x−a)3:s(5)=(5−4)(5−5)2Perform the calculation:s(5)=(1)(0)2s(5)=0
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