Verified answer

f(x) = ax² + bx + c

f(2x + 3) = a(2x+3)² + b*(2x + 3) + c

a*(4x² + 12x + 9) + 2bx + 3b + c = 2x² - 4x +1

4a = 2

a = 1/2

6x + 2bx = - 4x

2b = -10

b = -5

9a + 3b + c = 1

9/2 - 15 + c = 1

c = 16 - 9/2 = 23/2

f(x) = (x² - 10x + 23)/2

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