Question

set up the integral to find the area of a unit circle

Answer 1

What are the upper and lower limits?

Answer 2

can we do it in polar coordinates?

Answer 3

can u show me another way

Answer 4

Other methods involve double integrals or trig substitution integrals.
Can you do either of those? If not there is not much point showing you.

Answer 5

Very sorry... typo above!
\[A=\int_{0}^{r} Cdr\]where C is the circumference. In this case r=1 leads to C=2pi so we have\[A=\int_{0}^{1}2\pi r dr\]

Answer 6

you need to keep the r in the integral...
You only sub in the 1 at the end of course!