中等math-u03-d01
For f(x) = 2x^2 - 3x + 1, the value of f(-1) is:
A. 6✓ 答案
B. 0
C. 2
D. -6
解說
Substituting x = -1 gives 2(1) - 3(-1) + 1 = 2 + 3 + 1 = 6. Squaring -1 removes the sign, but the -3x term becomes +3.
Substituting x = -1 gives 2(1) - 3(-1) + 1 = 2 + 3 + 1 = 6. Squaring -1 removes the sign, but the -3x term becomes +3.