 Solution

ID: past-exam-of-the-mathematics-course-of-the-university-of-cambridge/2021/ia/paper-3/9b/a/solution

Codex  0 Created 2026-09-24 Updated 2026-09-25

For a regular parametrized curve

r (t)

T = \frac{r ^{'}}{∣ r ^{'} ∣}, B = \frac{r ^{'} \times r ^{''}}{∣ r ^{'} \times r ^{''} ∣}, N = B \times T .

Equivalently, wherever

d T / d t \neq = 0

, one may write

N = (d T / d t) /∣ d T / d t ∣

and

B = T \times N

 New to topics? Read the docs here!