Question

If f(x) = 2x3 - 4x2 + 4x + C and f(2) = 7, what is the value of C?

Answer 1

c = - 1

substitute x = 2 into f(x ) and equate to 7

2(2)³ - 4(2)² + 4(2) + c = 7

16 - 16 + 8 + c = 7

8 + c = 7

subtract 8 from both sides

c = 7 - 8 = - 1