Final answer:
To find f(x+a) when f(x) is given as ax + bx², we must substitute x with x+a and simplify. The correct expression for f(x+a) involves expanding the substitution and simplifying to get f(x+a) = f(x) + a + 2abx + ba². Therefore the Correct Answer is Option.A.
Step-by-step explanation:
The question asks for the expression for f(x+a) given that f(x) = ax + bx². To find f(x+a), we substitute x with x+a in the function.
The substitution gives us:
f(x+a) = a(x+a) + b(x+a)²
= ax + aa + b(x² + 2ax + a²)
= ax + a² + bx² + 2abx + ba²
Simplifying this expression:
f(x+a) = ax + a² + bx² + 2abx + ba²
= ax + a + bx² + 2abx + ba² (since a² = a)
We group like terms together:
f(x+a) = (ax + bx²) + (a + 2abx + ba²)
Since we know that ax + bx² is equal to f(x), we can write:
f(x+a) = f(x) + a + 2abx + ba²
Therefore, the correct option is not listed above directly, but the closest option, if corrected for typos, would be:
- A) f(x+a) = a(x+a) + b(x+a)²