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Given f(x)=x²+x+1 and h(x)=8x+5, evaluate the composite function. f[h(x)]

User SuperUser
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Final Answer:

The composite function f[h(x)] is equal to (8x + 5)² + (8x + 5) + 1.

Step-by-step explanation:

To evaluate the composite function f[h(x)], we substitute h(x) into f(x). The given functions are f(x) = x² + x + 1 and h(x) = 8x + 5. So, replacing x in f(x) with h(x), we get f[h(x)] = f(8x + 5). Substituting 8x + 5 into the expression for f(x), we obtain (8x + 5)² + (8x + 5) + 1.

Now, let's expand and simplify the expression.

(8x + 5)² = (8x + 5)(8x + 5) = 64x² + 40x + 40x + 25 = 64x² + 80x + 25.

Therefore, f[h(x)] = (8x + 5)² + (8x + 5) + 1 = 64x² + 80x + 25 + 8x + 5 + 1 = 64x² + 88x + 31.

In conclusion, the composite function f[h(x)] is equal to 64x² + 88x + 31. This result is obtained by substituting the expression for h(x) into the function f(x), followed by expanding and simplifying the resulting expression.

User Xierui
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