Is f(x)=2x3f(x) = 2x^3f(x)=2x3 one-to-one on R\mathbb{R}R?
Yes, strictly increasing
No, f(1)=f(−1)f(1) = f(-1)f(1)=f(−1)
Yes, f′≥0f' \ge 0f′≥0
No, has local extremum