Question

Find the total length of the cardioid:
r = 4 (1 + cos x)

Help please

Answer 1

Cardiods in polar form look like:
\[r = 2a(1 + \cos\theta)\]

The length is 16a

Answer 2

need the working :/

Answer 3

depending on what math you're in, the arc length of any curve defined in polar coordinates is given by
\[\int\limits_a^b \sqrt{r^2+\left(\frac{dr}{d\theta}\right)^2} d\theta\]