MHB Area Inside Circle x^2+y^2=a^2 Above b=7

[wonguyen1995]

Find area inside circle x^2+y^2=a^2, above 7=b, -a \le b \le a ?? i think f of y right?
(-a to a) minus (-a to b)?

 

[Evgeny.Makarov]

Find area inside circle x^2+y^2=a^2, above 7=b, -a \le b \le a

Maybe it's a typo and should read "above $y=b$". That is, find the area inside the circle $x^2+y^2=a^2$ that is located above the line $y=b$, where $-a\le b\le a$.

?? i think f of y right?
(-a to a) minus (-a to b)?

Sorry, I don't understand your remark.

 

[wonguyen1995]

Maybe it's a typo and should read "above $y=b$". That is, find the area inside the circle $x^2+y^2=a^2$ that is located above the line $y=b$, where $-a\le b\le a$.

Sorry, I don't understand your remark.

That is it, i mistake.
so can you help me??

 

[Evgeny.Makarov]

Do you need a solution that uses integral? It's easier to find the area geometrically as described in Wikipedia using the fact that the area of a triangle with sides $u$ and $v$ and angle $\varphi$ between them is $\frac{1}{2}uv\sin\varphi$.